SemaDecl.cpp revision a5bcdba68268ce8933b79b3676450d804ddba196
1//===--- SemaDecl.cpp - Semantic Analysis for Declarations ----------------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "clang/AST/APValue.h" 16#include "clang/AST/ASTConsumer.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/AST/DeclObjC.h" 19#include "clang/AST/DeclTemplate.h" 20#include "clang/AST/ExprCXX.h" 21#include "clang/Parse/DeclSpec.h" 22#include "clang/Basic/TargetInfo.h" 23#include "clang/Basic/SourceManager.h" 24// FIXME: layering (ideally, Sema shouldn't be dependent on Lex API's) 25#include "clang/Lex/Preprocessor.h" 26#include "clang/Lex/HeaderSearch.h" 27#include "llvm/ADT/SmallSet.h" 28#include "llvm/ADT/STLExtras.h" 29#include <algorithm> 30#include <functional> 31using namespace clang; 32 33/// getDeclName - Return a pretty name for the specified decl if possible, or 34/// an empty string if not. This is used for pretty crash reporting. 35std::string Sema::getDeclName(DeclPtrTy d) { 36 Decl *D = d.getAs<Decl>(); 37 if (NamedDecl *DN = dyn_cast_or_null<NamedDecl>(D)) 38 return DN->getQualifiedNameAsString(); 39 return ""; 40} 41 42Sema::DeclGroupPtrTy Sema::ConvertDeclToDeclGroup(DeclPtrTy Ptr) { 43 return DeclGroupPtrTy::make(DeclGroupRef(Ptr.getAs<Decl>())); 44} 45 46/// \brief If the identifier refers to a type name within this scope, 47/// return the declaration of that type. 48/// 49/// This routine performs ordinary name lookup of the identifier II 50/// within the given scope, with optional C++ scope specifier SS, to 51/// determine whether the name refers to a type. If so, returns an 52/// opaque pointer (actually a QualType) corresponding to that 53/// type. Otherwise, returns NULL. 54/// 55/// If name lookup results in an ambiguity, this routine will complain 56/// and then return NULL. 57Sema::TypeTy *Sema::getTypeName(IdentifierInfo &II, SourceLocation NameLoc, 58 Scope *S, const CXXScopeSpec *SS) { 59 // C++ [temp.res]p3: 60 // A qualified-id that refers to a type and in which the 61 // nested-name-specifier depends on a template-parameter (14.6.2) 62 // shall be prefixed by the keyword typename to indicate that the 63 // qualified-id denotes a type, forming an 64 // elaborated-type-specifier (7.1.5.3). 65 // 66 // We therefore do not perform any name lookup up SS is a dependent 67 // scope name. FIXME: we will need to perform a special kind of 68 // lookup if the scope specifier names a member of the current 69 // instantiation. 70 if (SS && isDependentScopeSpecifier(*SS)) 71 return 0; 72 73 NamedDecl *IIDecl = 0; 74 LookupResult Result = LookupParsedName(S, SS, &II, LookupOrdinaryName, 75 false, false); 76 switch (Result.getKind()) { 77 case LookupResult::NotFound: 78 case LookupResult::FoundOverloaded: 79 return 0; 80 81 case LookupResult::AmbiguousBaseSubobjectTypes: 82 case LookupResult::AmbiguousBaseSubobjects: 83 case LookupResult::AmbiguousReference: { 84 // Look to see if we have a type anywhere in the list of results. 85 for (LookupResult::iterator Res = Result.begin(), ResEnd = Result.end(); 86 Res != ResEnd; ++Res) { 87 if (isa<TypeDecl>(*Res) || isa<ObjCInterfaceDecl>(*Res)) { 88 if (!IIDecl || 89 (*Res)->getLocation().getRawEncoding() < 90 IIDecl->getLocation().getRawEncoding()) 91 IIDecl = *Res; 92 } 93 } 94 95 if (!IIDecl) { 96 // None of the entities we found is a type, so there is no way 97 // to even assume that the result is a type. In this case, don't 98 // complain about the ambiguity. The parser will either try to 99 // perform this lookup again (e.g., as an object name), which 100 // will produce the ambiguity, or will complain that it expected 101 // a type name. 102 Result.Destroy(); 103 return 0; 104 } 105 106 // We found a type within the ambiguous lookup; diagnose the 107 // ambiguity and then return that type. This might be the right 108 // answer, or it might not be, but it suppresses any attempt to 109 // perform the name lookup again. 110 DiagnoseAmbiguousLookup(Result, DeclarationName(&II), NameLoc); 111 break; 112 } 113 114 case LookupResult::Found: 115 IIDecl = Result.getAsDecl(); 116 break; 117 } 118 119 if (IIDecl) { 120 QualType T; 121 122 if (TypeDecl *TD = dyn_cast<TypeDecl>(IIDecl)) { 123 // Check whether we can use this type 124 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 125 126 T = Context.getTypeDeclType(TD); 127 } else if (ObjCInterfaceDecl *IDecl = dyn_cast<ObjCInterfaceDecl>(IIDecl)) { 128 // Check whether we can use this interface. 129 (void)DiagnoseUseOfDecl(IIDecl, NameLoc); 130 131 T = Context.getObjCInterfaceType(IDecl); 132 } else 133 return 0; 134 135 if (SS) 136 T = getQualifiedNameType(*SS, T); 137 138 return T.getAsOpaquePtr(); 139 } 140 141 return 0; 142} 143 144/// isTagName() - This method is called *for error recovery purposes only* 145/// to determine if the specified name is a valid tag name ("struct foo"). If 146/// so, this returns the TST for the tag corresponding to it (TST_enum, 147/// TST_union, TST_struct, TST_class). This is used to diagnose cases in C 148/// where the user forgot to specify the tag. 149DeclSpec::TST Sema::isTagName(IdentifierInfo &II, Scope *S) { 150 // Do a tag name lookup in this scope. 151 LookupResult R = LookupName(S, &II, LookupTagName, false, false); 152 if (R.getKind() == LookupResult::Found) 153 if (const TagDecl *TD = dyn_cast<TagDecl>(R.getAsDecl())) { 154 switch (TD->getTagKind()) { 155 case TagDecl::TK_struct: return DeclSpec::TST_struct; 156 case TagDecl::TK_union: return DeclSpec::TST_union; 157 case TagDecl::TK_class: return DeclSpec::TST_class; 158 case TagDecl::TK_enum: return DeclSpec::TST_enum; 159 } 160 } 161 162 return DeclSpec::TST_unspecified; 163} 164 165 166 167DeclContext *Sema::getContainingDC(DeclContext *DC) { 168 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) { 169 // A C++ out-of-line method will return to the file declaration context. 170 if (MD->isOutOfLineDefinition()) 171 return MD->getLexicalDeclContext(); 172 173 // A C++ inline method is parsed *after* the topmost class it was declared 174 // in is fully parsed (it's "complete"). 175 // The parsing of a C++ inline method happens at the declaration context of 176 // the topmost (non-nested) class it is lexically declared in. 177 assert(isa<CXXRecordDecl>(MD->getParent()) && "C++ method not in Record."); 178 DC = MD->getParent(); 179 while (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(DC->getLexicalParent())) 180 DC = RD; 181 182 // Return the declaration context of the topmost class the inline method is 183 // declared in. 184 return DC; 185 } 186 187 if (isa<ObjCMethodDecl>(DC)) 188 return Context.getTranslationUnitDecl(); 189 190 return DC->getLexicalParent(); 191} 192 193void Sema::PushDeclContext(Scope *S, DeclContext *DC) { 194 assert(getContainingDC(DC) == CurContext && 195 "The next DeclContext should be lexically contained in the current one."); 196 CurContext = DC; 197 S->setEntity(DC); 198} 199 200void Sema::PopDeclContext() { 201 assert(CurContext && "DeclContext imbalance!"); 202 203 CurContext = getContainingDC(CurContext); 204} 205 206/// \brief Determine whether we allow overloading of the function 207/// PrevDecl with another declaration. 208/// 209/// This routine determines whether overloading is possible, not 210/// whether some new function is actually an overload. It will return 211/// true in C++ (where we can always provide overloads) or, as an 212/// extension, in C when the previous function is already an 213/// overloaded function declaration or has the "overloadable" 214/// attribute. 215static bool AllowOverloadingOfFunction(Decl *PrevDecl, ASTContext &Context) { 216 if (Context.getLangOptions().CPlusPlus) 217 return true; 218 219 if (isa<OverloadedFunctionDecl>(PrevDecl)) 220 return true; 221 222 return PrevDecl->getAttr<OverloadableAttr>() != 0; 223} 224 225/// Add this decl to the scope shadowed decl chains. 226void Sema::PushOnScopeChains(NamedDecl *D, Scope *S) { 227 // Move up the scope chain until we find the nearest enclosing 228 // non-transparent context. The declaration will be introduced into this 229 // scope. 230 while (S->getEntity() && 231 ((DeclContext *)S->getEntity())->isTransparentContext()) 232 S = S->getParent(); 233 234 S->AddDecl(DeclPtrTy::make(D)); 235 236 // Add scoped declarations into their context, so that they can be 237 // found later. Declarations without a context won't be inserted 238 // into any context. 239 CurContext->addDecl(Context, D); 240 241 // C++ [basic.scope]p4: 242 // -- exactly one declaration shall declare a class name or 243 // enumeration name that is not a typedef name and the other 244 // declarations shall all refer to the same object or 245 // enumerator, or all refer to functions and function templates; 246 // in this case the class name or enumeration name is hidden. 247 if (TagDecl *TD = dyn_cast<TagDecl>(D)) { 248 // We are pushing the name of a tag (enum or class). 249 if (CurContext->getLookupContext() 250 == TD->getDeclContext()->getLookupContext()) { 251 // We're pushing the tag into the current context, which might 252 // require some reshuffling in the identifier resolver. 253 IdentifierResolver::iterator 254 I = IdResolver.begin(TD->getDeclName()), 255 IEnd = IdResolver.end(); 256 if (I != IEnd && isDeclInScope(*I, CurContext, S)) { 257 NamedDecl *PrevDecl = *I; 258 for (; I != IEnd && isDeclInScope(*I, CurContext, S); 259 PrevDecl = *I, ++I) { 260 if (TD->declarationReplaces(*I)) { 261 // This is a redeclaration. Remove it from the chain and 262 // break out, so that we'll add in the shadowed 263 // declaration. 264 S->RemoveDecl(DeclPtrTy::make(*I)); 265 if (PrevDecl == *I) { 266 IdResolver.RemoveDecl(*I); 267 IdResolver.AddDecl(TD); 268 return; 269 } else { 270 IdResolver.RemoveDecl(*I); 271 break; 272 } 273 } 274 } 275 276 // There is already a declaration with the same name in the same 277 // scope, which is not a tag declaration. It must be found 278 // before we find the new declaration, so insert the new 279 // declaration at the end of the chain. 280 IdResolver.AddShadowedDecl(TD, PrevDecl); 281 282 return; 283 } 284 } 285 } else if (isa<FunctionDecl>(D) && 286 AllowOverloadingOfFunction(D, Context)) { 287 // We are pushing the name of a function, which might be an 288 // overloaded name. 289 FunctionDecl *FD = cast<FunctionDecl>(D); 290 IdentifierResolver::iterator Redecl 291 = std::find_if(IdResolver.begin(FD->getDeclName()), 292 IdResolver.end(), 293 std::bind1st(std::mem_fun(&NamedDecl::declarationReplaces), 294 FD)); 295 if (Redecl != IdResolver.end() && 296 S->isDeclScope(DeclPtrTy::make(*Redecl))) { 297 // There is already a declaration of a function on our 298 // IdResolver chain. Replace it with this declaration. 299 S->RemoveDecl(DeclPtrTy::make(*Redecl)); 300 IdResolver.RemoveDecl(*Redecl); 301 } 302 } 303 304 IdResolver.AddDecl(D); 305} 306 307void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) { 308 if (S->decl_empty()) return; 309 assert((S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) && 310 "Scope shouldn't contain decls!"); 311 312 for (Scope::decl_iterator I = S->decl_begin(), E = S->decl_end(); 313 I != E; ++I) { 314 Decl *TmpD = (*I).getAs<Decl>(); 315 assert(TmpD && "This decl didn't get pushed??"); 316 317 assert(isa<NamedDecl>(TmpD) && "Decl isn't NamedDecl?"); 318 NamedDecl *D = cast<NamedDecl>(TmpD); 319 320 if (!D->getDeclName()) continue; 321 322 // Remove this name from our lexical scope. 323 IdResolver.RemoveDecl(D); 324 } 325} 326 327/// getObjCInterfaceDecl - Look up a for a class declaration in the scope. 328/// return 0 if one not found. 329ObjCInterfaceDecl *Sema::getObjCInterfaceDecl(IdentifierInfo *Id) { 330 // The third "scope" argument is 0 since we aren't enabling lazy built-in 331 // creation from this context. 332 NamedDecl *IDecl = LookupName(TUScope, Id, LookupOrdinaryName); 333 334 return dyn_cast_or_null<ObjCInterfaceDecl>(IDecl); 335} 336 337/// getNonFieldDeclScope - Retrieves the innermost scope, starting 338/// from S, where a non-field would be declared. This routine copes 339/// with the difference between C and C++ scoping rules in structs and 340/// unions. For example, the following code is well-formed in C but 341/// ill-formed in C++: 342/// @code 343/// struct S6 { 344/// enum { BAR } e; 345/// }; 346/// 347/// void test_S6() { 348/// struct S6 a; 349/// a.e = BAR; 350/// } 351/// @endcode 352/// For the declaration of BAR, this routine will return a different 353/// scope. The scope S will be the scope of the unnamed enumeration 354/// within S6. In C++, this routine will return the scope associated 355/// with S6, because the enumeration's scope is a transparent 356/// context but structures can contain non-field names. In C, this 357/// routine will return the translation unit scope, since the 358/// enumeration's scope is a transparent context and structures cannot 359/// contain non-field names. 360Scope *Sema::getNonFieldDeclScope(Scope *S) { 361 while (((S->getFlags() & Scope::DeclScope) == 0) || 362 (S->getEntity() && 363 ((DeclContext *)S->getEntity())->isTransparentContext()) || 364 (S->isClassScope() && !getLangOptions().CPlusPlus)) 365 S = S->getParent(); 366 return S; 367} 368 369void Sema::InitBuiltinVaListType() { 370 if (!Context.getBuiltinVaListType().isNull()) 371 return; 372 373 IdentifierInfo *VaIdent = &Context.Idents.get("__builtin_va_list"); 374 NamedDecl *VaDecl = LookupName(TUScope, VaIdent, LookupOrdinaryName); 375 TypedefDecl *VaTypedef = cast<TypedefDecl>(VaDecl); 376 Context.setBuiltinVaListType(Context.getTypedefType(VaTypedef)); 377} 378 379/// LazilyCreateBuiltin - The specified Builtin-ID was first used at 380/// file scope. lazily create a decl for it. ForRedeclaration is true 381/// if we're creating this built-in in anticipation of redeclaring the 382/// built-in. 383NamedDecl *Sema::LazilyCreateBuiltin(IdentifierInfo *II, unsigned bid, 384 Scope *S, bool ForRedeclaration, 385 SourceLocation Loc) { 386 Builtin::ID BID = (Builtin::ID)bid; 387 388 if (Context.BuiltinInfo.hasVAListUse(BID)) 389 InitBuiltinVaListType(); 390 391 Builtin::Context::GetBuiltinTypeError Error; 392 QualType R = Context.BuiltinInfo.GetBuiltinType(BID, Context, Error); 393 switch (Error) { 394 case Builtin::Context::GE_None: 395 // Okay 396 break; 397 398 case Builtin::Context::GE_Missing_FILE: 399 if (ForRedeclaration) 400 Diag(Loc, diag::err_implicit_decl_requires_stdio) 401 << Context.BuiltinInfo.GetName(BID); 402 return 0; 403 } 404 405 if (!ForRedeclaration && Context.BuiltinInfo.isPredefinedLibFunction(BID)) { 406 Diag(Loc, diag::ext_implicit_lib_function_decl) 407 << Context.BuiltinInfo.GetName(BID) 408 << R; 409 if (Context.BuiltinInfo.getHeaderName(BID) && 410 Diags.getDiagnosticLevel(diag::ext_implicit_lib_function_decl) 411 != Diagnostic::Ignored) 412 Diag(Loc, diag::note_please_include_header) 413 << Context.BuiltinInfo.getHeaderName(BID) 414 << Context.BuiltinInfo.GetName(BID); 415 } 416 417 FunctionDecl *New = FunctionDecl::Create(Context, 418 Context.getTranslationUnitDecl(), 419 Loc, II, R, 420 FunctionDecl::Extern, false, 421 /*hasPrototype=*/true); 422 New->setImplicit(); 423 424 // Create Decl objects for each parameter, adding them to the 425 // FunctionDecl. 426 if (FunctionProtoType *FT = dyn_cast<FunctionProtoType>(R)) { 427 llvm::SmallVector<ParmVarDecl*, 16> Params; 428 for (unsigned i = 0, e = FT->getNumArgs(); i != e; ++i) 429 Params.push_back(ParmVarDecl::Create(Context, New, SourceLocation(), 0, 430 FT->getArgType(i), VarDecl::None, 0)); 431 New->setParams(Context, &Params[0], Params.size()); 432 } 433 434 AddKnownFunctionAttributes(New); 435 436 // TUScope is the translation-unit scope to insert this function into. 437 // FIXME: This is hideous. We need to teach PushOnScopeChains to 438 // relate Scopes to DeclContexts, and probably eliminate CurContext 439 // entirely, but we're not there yet. 440 DeclContext *SavedContext = CurContext; 441 CurContext = Context.getTranslationUnitDecl(); 442 PushOnScopeChains(New, TUScope); 443 CurContext = SavedContext; 444 return New; 445} 446 447/// GetStdNamespace - This method gets the C++ "std" namespace. This is where 448/// everything from the standard library is defined. 449NamespaceDecl *Sema::GetStdNamespace() { 450 if (!StdNamespace) { 451 IdentifierInfo *StdIdent = &PP.getIdentifierTable().get("std"); 452 DeclContext *Global = Context.getTranslationUnitDecl(); 453 Decl *Std = LookupQualifiedName(Global, StdIdent, LookupNamespaceName); 454 StdNamespace = dyn_cast_or_null<NamespaceDecl>(Std); 455 } 456 return StdNamespace; 457} 458 459/// MergeTypeDefDecl - We just parsed a typedef 'New' which has the 460/// same name and scope as a previous declaration 'Old'. Figure out 461/// how to resolve this situation, merging decls or emitting 462/// diagnostics as appropriate. Returns true if there was an error, 463/// false otherwise. 464/// 465bool Sema::MergeTypeDefDecl(TypedefDecl *New, Decl *OldD) { 466 bool objc_types = false; 467 // Allow multiple definitions for ObjC built-in typedefs. 468 // FIXME: Verify the underlying types are equivalent! 469 if (getLangOptions().ObjC1) { 470 const IdentifierInfo *TypeID = New->getIdentifier(); 471 switch (TypeID->getLength()) { 472 default: break; 473 case 2: 474 if (!TypeID->isStr("id")) 475 break; 476 Context.setObjCIdType(New); 477 objc_types = true; 478 break; 479 case 5: 480 if (!TypeID->isStr("Class")) 481 break; 482 Context.setObjCClassType(New); 483 objc_types = true; 484 return false; 485 case 3: 486 if (!TypeID->isStr("SEL")) 487 break; 488 Context.setObjCSelType(New); 489 objc_types = true; 490 return false; 491 case 8: 492 if (!TypeID->isStr("Protocol")) 493 break; 494 Context.setObjCProtoType(New->getUnderlyingType()); 495 objc_types = true; 496 return false; 497 } 498 // Fall through - the typedef name was not a builtin type. 499 } 500 // Verify the old decl was also a type. 501 TypeDecl *Old = dyn_cast<TypeDecl>(OldD); 502 if (!Old) { 503 Diag(New->getLocation(), diag::err_redefinition_different_kind) 504 << New->getDeclName(); 505 if (!objc_types) 506 Diag(OldD->getLocation(), diag::note_previous_definition); 507 return true; 508 } 509 510 // Determine the "old" type we'll use for checking and diagnostics. 511 QualType OldType; 512 if (TypedefDecl *OldTypedef = dyn_cast<TypedefDecl>(Old)) 513 OldType = OldTypedef->getUnderlyingType(); 514 else 515 OldType = Context.getTypeDeclType(Old); 516 517 // If the typedef types are not identical, reject them in all languages and 518 // with any extensions enabled. 519 520 if (OldType != New->getUnderlyingType() && 521 Context.getCanonicalType(OldType) != 522 Context.getCanonicalType(New->getUnderlyingType())) { 523 Diag(New->getLocation(), diag::err_redefinition_different_typedef) 524 << New->getUnderlyingType() << OldType; 525 if (!objc_types) 526 Diag(Old->getLocation(), diag::note_previous_definition); 527 return true; 528 } 529 if (objc_types) return false; 530 if (getLangOptions().Microsoft) return false; 531 532 // C++ [dcl.typedef]p2: 533 // In a given non-class scope, a typedef specifier can be used to 534 // redefine the name of any type declared in that scope to refer 535 // to the type to which it already refers. 536 if (getLangOptions().CPlusPlus && !isa<CXXRecordDecl>(CurContext)) 537 return false; 538 539 // In C, redeclaration of a type is a constraint violation (6.7.2.3p1). 540 // Apparently GCC, Intel, and Sun all silently ignore the redeclaration if 541 // *either* declaration is in a system header. The code below implements 542 // this adhoc compatibility rule. FIXME: The following code will not 543 // work properly when compiling ".i" files (containing preprocessed output). 544 if (PP.getDiagnostics().getSuppressSystemWarnings()) { 545 SourceManager &SrcMgr = Context.getSourceManager(); 546 if (SrcMgr.isInSystemHeader(Old->getLocation())) 547 return false; 548 if (SrcMgr.isInSystemHeader(New->getLocation())) 549 return false; 550 } 551 552 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 553 Diag(Old->getLocation(), diag::note_previous_definition); 554 return true; 555} 556 557/// DeclhasAttr - returns true if decl Declaration already has the target 558/// attribute. 559static bool DeclHasAttr(const Decl *decl, const Attr *target) { 560 for (const Attr *attr = decl->getAttrs(); attr; attr = attr->getNext()) 561 if (attr->getKind() == target->getKind()) 562 return true; 563 564 return false; 565} 566 567/// MergeAttributes - append attributes from the Old decl to the New one. 568static void MergeAttributes(Decl *New, Decl *Old, ASTContext &C) { 569 Attr *attr = const_cast<Attr*>(Old->getAttrs()); 570 571 while (attr) { 572 Attr *tmp = attr; 573 attr = attr->getNext(); 574 575 if (!DeclHasAttr(New, tmp) && tmp->isMerged()) { 576 tmp->setInherited(true); 577 New->addAttr(tmp); 578 } else { 579 tmp->setNext(0); 580 tmp->Destroy(C); 581 } 582 } 583 584 Old->invalidateAttrs(); 585} 586 587/// Used in MergeFunctionDecl to keep track of function parameters in 588/// C. 589struct GNUCompatibleParamWarning { 590 ParmVarDecl *OldParm; 591 ParmVarDecl *NewParm; 592 QualType PromotedType; 593}; 594 595/// MergeFunctionDecl - We just parsed a function 'New' from 596/// declarator D which has the same name and scope as a previous 597/// declaration 'Old'. Figure out how to resolve this situation, 598/// merging decls or emitting diagnostics as appropriate. 599/// 600/// In C++, New and Old must be declarations that are not 601/// overloaded. Use IsOverload to determine whether New and Old are 602/// overloaded, and to select the Old declaration that New should be 603/// merged with. 604/// 605/// Returns true if there was an error, false otherwise. 606bool Sema::MergeFunctionDecl(FunctionDecl *New, Decl *OldD) { 607 assert(!isa<OverloadedFunctionDecl>(OldD) && 608 "Cannot merge with an overloaded function declaration"); 609 610 // Verify the old decl was also a function. 611 FunctionDecl *Old = dyn_cast<FunctionDecl>(OldD); 612 if (!Old) { 613 Diag(New->getLocation(), diag::err_redefinition_different_kind) 614 << New->getDeclName(); 615 Diag(OldD->getLocation(), diag::note_previous_definition); 616 return true; 617 } 618 619 // Determine whether the previous declaration was a definition, 620 // implicit declaration, or a declaration. 621 diag::kind PrevDiag; 622 if (Old->isThisDeclarationADefinition()) 623 PrevDiag = diag::note_previous_definition; 624 else if (Old->isImplicit()) 625 PrevDiag = diag::note_previous_implicit_declaration; 626 else 627 PrevDiag = diag::note_previous_declaration; 628 629 QualType OldQType = Context.getCanonicalType(Old->getType()); 630 QualType NewQType = Context.getCanonicalType(New->getType()); 631 632 if (!isa<CXXMethodDecl>(New) && !isa<CXXMethodDecl>(Old) && 633 New->getStorageClass() == FunctionDecl::Static && 634 Old->getStorageClass() != FunctionDecl::Static) { 635 Diag(New->getLocation(), diag::err_static_non_static) 636 << New; 637 Diag(Old->getLocation(), PrevDiag); 638 return true; 639 } 640 641 if (getLangOptions().CPlusPlus) { 642 // (C++98 13.1p2): 643 // Certain function declarations cannot be overloaded: 644 // -- Function declarations that differ only in the return type 645 // cannot be overloaded. 646 QualType OldReturnType 647 = cast<FunctionType>(OldQType.getTypePtr())->getResultType(); 648 QualType NewReturnType 649 = cast<FunctionType>(NewQType.getTypePtr())->getResultType(); 650 if (OldReturnType != NewReturnType) { 651 Diag(New->getLocation(), diag::err_ovl_diff_return_type); 652 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 653 return true; 654 } 655 656 const CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 657 const CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 658 if (OldMethod && NewMethod && 659 OldMethod->getLexicalDeclContext() == 660 NewMethod->getLexicalDeclContext()) { 661 // -- Member function declarations with the same name and the 662 // same parameter types cannot be overloaded if any of them 663 // is a static member function declaration. 664 if (OldMethod->isStatic() || NewMethod->isStatic()) { 665 Diag(New->getLocation(), diag::err_ovl_static_nonstatic_member); 666 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 667 return true; 668 } 669 670 // C++ [class.mem]p1: 671 // [...] A member shall not be declared twice in the 672 // member-specification, except that a nested class or member 673 // class template can be declared and then later defined. 674 unsigned NewDiag; 675 if (isa<CXXConstructorDecl>(OldMethod)) 676 NewDiag = diag::err_constructor_redeclared; 677 else if (isa<CXXDestructorDecl>(NewMethod)) 678 NewDiag = diag::err_destructor_redeclared; 679 else if (isa<CXXConversionDecl>(NewMethod)) 680 NewDiag = diag::err_conv_function_redeclared; 681 else 682 NewDiag = diag::err_member_redeclared; 683 684 Diag(New->getLocation(), NewDiag); 685 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 686 } 687 688 // (C++98 8.3.5p3): 689 // All declarations for a function shall agree exactly in both the 690 // return type and the parameter-type-list. 691 if (OldQType == NewQType) 692 return MergeCompatibleFunctionDecls(New, Old); 693 694 // Fall through for conflicting redeclarations and redefinitions. 695 } 696 697 // C: Function types need to be compatible, not identical. This handles 698 // duplicate function decls like "void f(int); void f(enum X);" properly. 699 if (!getLangOptions().CPlusPlus && 700 Context.typesAreCompatible(OldQType, NewQType)) { 701 const FunctionType *OldFuncType = OldQType->getAsFunctionType(); 702 const FunctionType *NewFuncType = NewQType->getAsFunctionType(); 703 const FunctionProtoType *OldProto = 0; 704 if (isa<FunctionNoProtoType>(NewFuncType) && 705 (OldProto = dyn_cast<FunctionProtoType>(OldFuncType))) { 706 // The old declaration provided a function prototype, but the 707 // new declaration does not. Merge in the prototype. 708 llvm::SmallVector<QualType, 16> ParamTypes(OldProto->arg_type_begin(), 709 OldProto->arg_type_end()); 710 NewQType = Context.getFunctionType(NewFuncType->getResultType(), 711 &ParamTypes[0], ParamTypes.size(), 712 OldProto->isVariadic(), 713 OldProto->getTypeQuals()); 714 New->setType(NewQType); 715 New->setInheritedPrototype(); 716 717 // Synthesize a parameter for each argument type. 718 llvm::SmallVector<ParmVarDecl*, 16> Params; 719 for (FunctionProtoType::arg_type_iterator 720 ParamType = OldProto->arg_type_begin(), 721 ParamEnd = OldProto->arg_type_end(); 722 ParamType != ParamEnd; ++ParamType) { 723 ParmVarDecl *Param = ParmVarDecl::Create(Context, New, 724 SourceLocation(), 0, 725 *ParamType, VarDecl::None, 726 0); 727 Param->setImplicit(); 728 Params.push_back(Param); 729 } 730 731 New->setParams(Context, &Params[0], Params.size()); 732 } 733 734 return MergeCompatibleFunctionDecls(New, Old); 735 } 736 737 // GNU C permits a K&R definition to follow a prototype declaration 738 // if the declared types of the parameters in the K&R definition 739 // match the types in the prototype declaration, even when the 740 // promoted types of the parameters from the K&R definition differ 741 // from the types in the prototype. GCC then keeps the types from 742 // the prototype. 743 if (!getLangOptions().CPlusPlus && 744 !getLangOptions().NoExtensions && 745 Old->hasPrototype() && !New->hasPrototype() && 746 New->getType()->getAsFunctionProtoType() && 747 Old->getNumParams() == New->getNumParams()) { 748 llvm::SmallVector<QualType, 16> ArgTypes; 749 llvm::SmallVector<GNUCompatibleParamWarning, 16> Warnings; 750 const FunctionProtoType *OldProto 751 = Old->getType()->getAsFunctionProtoType(); 752 const FunctionProtoType *NewProto 753 = New->getType()->getAsFunctionProtoType(); 754 755 // Determine whether this is the GNU C extension. 756 bool GNUCompatible = 757 Context.typesAreCompatible(OldProto->getResultType(), 758 NewProto->getResultType()) && 759 (OldProto->isVariadic() == NewProto->isVariadic()); 760 for (unsigned Idx = 0, End = Old->getNumParams(); 761 GNUCompatible && Idx != End; ++Idx) { 762 ParmVarDecl *OldParm = Old->getParamDecl(Idx); 763 ParmVarDecl *NewParm = New->getParamDecl(Idx); 764 if (Context.typesAreCompatible(OldParm->getType(), 765 NewProto->getArgType(Idx))) { 766 ArgTypes.push_back(NewParm->getType()); 767 } else if (Context.typesAreCompatible(OldParm->getType(), 768 NewParm->getType())) { 769 GNUCompatibleParamWarning Warn 770 = { OldParm, NewParm, NewProto->getArgType(Idx) }; 771 Warnings.push_back(Warn); 772 ArgTypes.push_back(NewParm->getType()); 773 } else 774 GNUCompatible = false; 775 } 776 777 if (GNUCompatible) { 778 for (unsigned Warn = 0; Warn < Warnings.size(); ++Warn) { 779 Diag(Warnings[Warn].NewParm->getLocation(), 780 diag::ext_param_promoted_not_compatible_with_prototype) 781 << Warnings[Warn].PromotedType 782 << Warnings[Warn].OldParm->getType(); 783 Diag(Warnings[Warn].OldParm->getLocation(), 784 diag::note_previous_declaration); 785 } 786 787 New->setType(Context.getFunctionType(NewProto->getResultType(), 788 &ArgTypes[0], ArgTypes.size(), 789 NewProto->isVariadic(), 790 NewProto->getTypeQuals())); 791 return MergeCompatibleFunctionDecls(New, Old); 792 } 793 794 // Fall through to diagnose conflicting types. 795 } 796 797 // A function that has already been declared has been redeclared or defined 798 // with a different type- show appropriate diagnostic 799 if (unsigned BuiltinID = Old->getBuiltinID(Context)) { 800 // The user has declared a builtin function with an incompatible 801 // signature. 802 if (Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 803 // The function the user is redeclaring is a library-defined 804 // function like 'malloc' or 'printf'. Warn about the 805 // redeclaration, then pretend that we don't know about this 806 // library built-in. 807 Diag(New->getLocation(), diag::warn_redecl_library_builtin) << New; 808 Diag(Old->getLocation(), diag::note_previous_builtin_declaration) 809 << Old << Old->getType(); 810 New->getIdentifier()->setBuiltinID(Builtin::NotBuiltin); 811 Old->setInvalidDecl(); 812 return false; 813 } 814 815 PrevDiag = diag::note_previous_builtin_declaration; 816 } 817 818 Diag(New->getLocation(), diag::err_conflicting_types) << New->getDeclName(); 819 Diag(Old->getLocation(), PrevDiag) << Old << Old->getType(); 820 return true; 821} 822 823/// \brief Completes the merge of two function declarations that are 824/// known to be compatible. 825/// 826/// This routine handles the merging of attributes and other 827/// properties of function declarations form the old declaration to 828/// the new declaration, once we know that New is in fact a 829/// redeclaration of Old. 830/// 831/// \returns false 832bool Sema::MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old) { 833 // Merge the attributes 834 MergeAttributes(New, Old, Context); 835 836 // Merge the storage class. 837 New->setStorageClass(Old->getStorageClass()); 838 839 // FIXME: need to implement inline semantics 840 841 // Merge "pure" flag. 842 if (Old->isPure()) 843 New->setPure(); 844 845 // Merge the "deleted" flag. 846 if (Old->isDeleted()) 847 New->setDeleted(); 848 849 if (getLangOptions().CPlusPlus) 850 return MergeCXXFunctionDecl(New, Old); 851 852 return false; 853} 854 855/// MergeVarDecl - We just parsed a variable 'New' which has the same name 856/// and scope as a previous declaration 'Old'. Figure out how to resolve this 857/// situation, merging decls or emitting diagnostics as appropriate. 858/// 859/// Tentative definition rules (C99 6.9.2p2) are checked by 860/// FinalizeDeclaratorGroup. Unfortunately, we can't analyze tentative 861/// definitions here, since the initializer hasn't been attached. 862/// 863bool Sema::MergeVarDecl(VarDecl *New, Decl *OldD) { 864 // Verify the old decl was also a variable. 865 VarDecl *Old = dyn_cast<VarDecl>(OldD); 866 if (!Old) { 867 Diag(New->getLocation(), diag::err_redefinition_different_kind) 868 << New->getDeclName(); 869 Diag(OldD->getLocation(), diag::note_previous_definition); 870 return true; 871 } 872 873 MergeAttributes(New, Old, Context); 874 875 // Merge the types 876 QualType MergedT = Context.mergeTypes(New->getType(), Old->getType()); 877 if (MergedT.isNull()) { 878 Diag(New->getLocation(), diag::err_redefinition_different_type) 879 << New->getDeclName(); 880 Diag(Old->getLocation(), diag::note_previous_definition); 881 return true; 882 } 883 New->setType(MergedT); 884 885 // C99 6.2.2p4: Check if we have a static decl followed by a non-static. 886 if (New->getStorageClass() == VarDecl::Static && 887 (Old->getStorageClass() == VarDecl::None || Old->hasExternalStorage())) { 888 Diag(New->getLocation(), diag::err_static_non_static) << New->getDeclName(); 889 Diag(Old->getLocation(), diag::note_previous_definition); 890 return true; 891 } 892 // C99 6.2.2p4: 893 // For an identifier declared with the storage-class specifier 894 // extern in a scope in which a prior declaration of that 895 // identifier is visible,23) if the prior declaration specifies 896 // internal or external linkage, the linkage of the identifier at 897 // the later declaration is the same as the linkage specified at 898 // the prior declaration. If no prior declaration is visible, or 899 // if the prior declaration specifies no linkage, then the 900 // identifier has external linkage. 901 if (New->hasExternalStorage() && Old->hasLinkage()) 902 /* Okay */; 903 else if (New->getStorageClass() != VarDecl::Static && 904 Old->getStorageClass() == VarDecl::Static) { 905 Diag(New->getLocation(), diag::err_non_static_static) << New->getDeclName(); 906 Diag(Old->getLocation(), diag::note_previous_definition); 907 return true; 908 } 909 910 // Variables with external linkage are analyzed in FinalizeDeclaratorGroup. 911 912 // FIXME: The test for external storage here seems wrong? We still 913 // need to check for mismatches. 914 if (!New->hasExternalStorage() && !New->isFileVarDecl() && 915 // Don't complain about out-of-line definitions of static members. 916 !(Old->getLexicalDeclContext()->isRecord() && 917 !New->getLexicalDeclContext()->isRecord())) { 918 Diag(New->getLocation(), diag::err_redefinition) << New->getDeclName(); 919 Diag(Old->getLocation(), diag::note_previous_definition); 920 return true; 921 } 922 923 // Keep a chain of previous declarations. 924 New->setPreviousDeclaration(Old); 925 926 return false; 927} 928 929/// CheckParmsForFunctionDef - Check that the parameters of the given 930/// function are appropriate for the definition of a function. This 931/// takes care of any checks that cannot be performed on the 932/// declaration itself, e.g., that the types of each of the function 933/// parameters are complete. 934bool Sema::CheckParmsForFunctionDef(FunctionDecl *FD) { 935 bool HasInvalidParm = false; 936 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 937 ParmVarDecl *Param = FD->getParamDecl(p); 938 939 // C99 6.7.5.3p4: the parameters in a parameter type list in a 940 // function declarator that is part of a function definition of 941 // that function shall not have incomplete type. 942 // 943 // This is also C++ [dcl.fct]p6. 944 if (!Param->isInvalidDecl() && 945 RequireCompleteType(Param->getLocation(), Param->getType(), 946 diag::err_typecheck_decl_incomplete_type)) { 947 Param->setInvalidDecl(); 948 HasInvalidParm = true; 949 } 950 951 // C99 6.9.1p5: If the declarator includes a parameter type list, the 952 // declaration of each parameter shall include an identifier. 953 if (Param->getIdentifier() == 0 && 954 !Param->isImplicit() && 955 !getLangOptions().CPlusPlus) 956 Diag(Param->getLocation(), diag::err_parameter_name_omitted); 957 } 958 959 return HasInvalidParm; 960} 961 962/// ParsedFreeStandingDeclSpec - This method is invoked when a declspec with 963/// no declarator (e.g. "struct foo;") is parsed. 964Sema::DeclPtrTy Sema::ParsedFreeStandingDeclSpec(Scope *S, DeclSpec &DS) { 965 // FIXME: Error on auto/register at file scope 966 // FIXME: Error on inline/virtual/explicit 967 // FIXME: Error on invalid restrict 968 // FIXME: Warn on useless const/volatile 969 // FIXME: Warn on useless static/extern/typedef/private_extern/mutable 970 // FIXME: Warn on useless attributes 971 972 TagDecl *Tag = 0; 973 if (DS.getTypeSpecType() == DeclSpec::TST_class || 974 DS.getTypeSpecType() == DeclSpec::TST_struct || 975 DS.getTypeSpecType() == DeclSpec::TST_union || 976 DS.getTypeSpecType() == DeclSpec::TST_enum) 977 Tag = dyn_cast<TagDecl>(static_cast<Decl *>(DS.getTypeRep())); 978 979 if (RecordDecl *Record = dyn_cast_or_null<RecordDecl>(Tag)) { 980 if (!Record->getDeclName() && Record->isDefinition() && 981 DS.getStorageClassSpec() != DeclSpec::SCS_typedef) { 982 if (getLangOptions().CPlusPlus || 983 Record->getDeclContext()->isRecord()) 984 return BuildAnonymousStructOrUnion(S, DS, Record); 985 986 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 987 << DS.getSourceRange(); 988 } 989 990 // Microsoft allows unnamed struct/union fields. Don't complain 991 // about them. 992 // FIXME: Should we support Microsoft's extensions in this area? 993 if (Record->getDeclName() && getLangOptions().Microsoft) 994 return DeclPtrTy::make(Tag); 995 } 996 997 if (!DS.isMissingDeclaratorOk() && 998 DS.getTypeSpecType() != DeclSpec::TST_error) { 999 // Warn about typedefs of enums without names, since this is an 1000 // extension in both Microsoft an GNU. 1001 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef && 1002 Tag && isa<EnumDecl>(Tag)) { 1003 Diag(DS.getSourceRange().getBegin(), diag::ext_typedef_without_a_name) 1004 << DS.getSourceRange(); 1005 return DeclPtrTy::make(Tag); 1006 } 1007 1008 Diag(DS.getSourceRange().getBegin(), diag::err_no_declarators) 1009 << DS.getSourceRange(); 1010 return DeclPtrTy(); 1011 } 1012 1013 return DeclPtrTy::make(Tag); 1014} 1015 1016/// InjectAnonymousStructOrUnionMembers - Inject the members of the 1017/// anonymous struct or union AnonRecord into the owning context Owner 1018/// and scope S. This routine will be invoked just after we realize 1019/// that an unnamed union or struct is actually an anonymous union or 1020/// struct, e.g., 1021/// 1022/// @code 1023/// union { 1024/// int i; 1025/// float f; 1026/// }; // InjectAnonymousStructOrUnionMembers called here to inject i and 1027/// // f into the surrounding scope.x 1028/// @endcode 1029/// 1030/// This routine is recursive, injecting the names of nested anonymous 1031/// structs/unions into the owning context and scope as well. 1032bool Sema::InjectAnonymousStructOrUnionMembers(Scope *S, DeclContext *Owner, 1033 RecordDecl *AnonRecord) { 1034 bool Invalid = false; 1035 for (RecordDecl::field_iterator F = AnonRecord->field_begin(Context), 1036 FEnd = AnonRecord->field_end(Context); 1037 F != FEnd; ++F) { 1038 if ((*F)->getDeclName()) { 1039 NamedDecl *PrevDecl = LookupQualifiedName(Owner, (*F)->getDeclName(), 1040 LookupOrdinaryName, true); 1041 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 1042 // C++ [class.union]p2: 1043 // The names of the members of an anonymous union shall be 1044 // distinct from the names of any other entity in the 1045 // scope in which the anonymous union is declared. 1046 unsigned diagKind 1047 = AnonRecord->isUnion()? diag::err_anonymous_union_member_redecl 1048 : diag::err_anonymous_struct_member_redecl; 1049 Diag((*F)->getLocation(), diagKind) 1050 << (*F)->getDeclName(); 1051 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 1052 Invalid = true; 1053 } else { 1054 // C++ [class.union]p2: 1055 // For the purpose of name lookup, after the anonymous union 1056 // definition, the members of the anonymous union are 1057 // considered to have been defined in the scope in which the 1058 // anonymous union is declared. 1059 Owner->makeDeclVisibleInContext(Context, *F); 1060 S->AddDecl(DeclPtrTy::make(*F)); 1061 IdResolver.AddDecl(*F); 1062 } 1063 } else if (const RecordType *InnerRecordType 1064 = (*F)->getType()->getAsRecordType()) { 1065 RecordDecl *InnerRecord = InnerRecordType->getDecl(); 1066 if (InnerRecord->isAnonymousStructOrUnion()) 1067 Invalid = Invalid || 1068 InjectAnonymousStructOrUnionMembers(S, Owner, InnerRecord); 1069 } 1070 } 1071 1072 return Invalid; 1073} 1074 1075/// ActOnAnonymousStructOrUnion - Handle the declaration of an 1076/// anonymous structure or union. Anonymous unions are a C++ feature 1077/// (C++ [class.union]) and a GNU C extension; anonymous structures 1078/// are a GNU C and GNU C++ extension. 1079Sema::DeclPtrTy Sema::BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS, 1080 RecordDecl *Record) { 1081 DeclContext *Owner = Record->getDeclContext(); 1082 1083 // Diagnose whether this anonymous struct/union is an extension. 1084 if (Record->isUnion() && !getLangOptions().CPlusPlus) 1085 Diag(Record->getLocation(), diag::ext_anonymous_union); 1086 else if (!Record->isUnion()) 1087 Diag(Record->getLocation(), diag::ext_anonymous_struct); 1088 1089 // C and C++ require different kinds of checks for anonymous 1090 // structs/unions. 1091 bool Invalid = false; 1092 if (getLangOptions().CPlusPlus) { 1093 const char* PrevSpec = 0; 1094 // C++ [class.union]p3: 1095 // Anonymous unions declared in a named namespace or in the 1096 // global namespace shall be declared static. 1097 if (DS.getStorageClassSpec() != DeclSpec::SCS_static && 1098 (isa<TranslationUnitDecl>(Owner) || 1099 (isa<NamespaceDecl>(Owner) && 1100 cast<NamespaceDecl>(Owner)->getDeclName()))) { 1101 Diag(Record->getLocation(), diag::err_anonymous_union_not_static); 1102 Invalid = true; 1103 1104 // Recover by adding 'static'. 1105 DS.SetStorageClassSpec(DeclSpec::SCS_static, SourceLocation(), PrevSpec); 1106 } 1107 // C++ [class.union]p3: 1108 // A storage class is not allowed in a declaration of an 1109 // anonymous union in a class scope. 1110 else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified && 1111 isa<RecordDecl>(Owner)) { 1112 Diag(DS.getStorageClassSpecLoc(), 1113 diag::err_anonymous_union_with_storage_spec); 1114 Invalid = true; 1115 1116 // Recover by removing the storage specifier. 1117 DS.SetStorageClassSpec(DeclSpec::SCS_unspecified, SourceLocation(), 1118 PrevSpec); 1119 } 1120 1121 // C++ [class.union]p2: 1122 // The member-specification of an anonymous union shall only 1123 // define non-static data members. [Note: nested types and 1124 // functions cannot be declared within an anonymous union. ] 1125 for (DeclContext::decl_iterator Mem = Record->decls_begin(Context), 1126 MemEnd = Record->decls_end(Context); 1127 Mem != MemEnd; ++Mem) { 1128 if (FieldDecl *FD = dyn_cast<FieldDecl>(*Mem)) { 1129 // C++ [class.union]p3: 1130 // An anonymous union shall not have private or protected 1131 // members (clause 11). 1132 if (FD->getAccess() == AS_protected || FD->getAccess() == AS_private) { 1133 Diag(FD->getLocation(), diag::err_anonymous_record_nonpublic_member) 1134 << (int)Record->isUnion() << (int)(FD->getAccess() == AS_protected); 1135 Invalid = true; 1136 } 1137 } else if ((*Mem)->isImplicit()) { 1138 // Any implicit members are fine. 1139 } else if (isa<TagDecl>(*Mem) && (*Mem)->getDeclContext() != Record) { 1140 // This is a type that showed up in an 1141 // elaborated-type-specifier inside the anonymous struct or 1142 // union, but which actually declares a type outside of the 1143 // anonymous struct or union. It's okay. 1144 } else if (RecordDecl *MemRecord = dyn_cast<RecordDecl>(*Mem)) { 1145 if (!MemRecord->isAnonymousStructOrUnion() && 1146 MemRecord->getDeclName()) { 1147 // This is a nested type declaration. 1148 Diag(MemRecord->getLocation(), diag::err_anonymous_record_with_type) 1149 << (int)Record->isUnion(); 1150 Invalid = true; 1151 } 1152 } else { 1153 // We have something that isn't a non-static data 1154 // member. Complain about it. 1155 unsigned DK = diag::err_anonymous_record_bad_member; 1156 if (isa<TypeDecl>(*Mem)) 1157 DK = diag::err_anonymous_record_with_type; 1158 else if (isa<FunctionDecl>(*Mem)) 1159 DK = diag::err_anonymous_record_with_function; 1160 else if (isa<VarDecl>(*Mem)) 1161 DK = diag::err_anonymous_record_with_static; 1162 Diag((*Mem)->getLocation(), DK) 1163 << (int)Record->isUnion(); 1164 Invalid = true; 1165 } 1166 } 1167 } 1168 1169 if (!Record->isUnion() && !Owner->isRecord()) { 1170 Diag(Record->getLocation(), diag::err_anonymous_struct_not_member) 1171 << (int)getLangOptions().CPlusPlus; 1172 Invalid = true; 1173 } 1174 1175 // Create a declaration for this anonymous struct/union. 1176 NamedDecl *Anon = 0; 1177 if (RecordDecl *OwningClass = dyn_cast<RecordDecl>(Owner)) { 1178 Anon = FieldDecl::Create(Context, OwningClass, Record->getLocation(), 1179 /*IdentifierInfo=*/0, 1180 Context.getTypeDeclType(Record), 1181 /*BitWidth=*/0, /*Mutable=*/false); 1182 Anon->setAccess(AS_public); 1183 if (getLangOptions().CPlusPlus) 1184 FieldCollector->Add(cast<FieldDecl>(Anon)); 1185 } else { 1186 VarDecl::StorageClass SC; 1187 switch (DS.getStorageClassSpec()) { 1188 default: assert(0 && "Unknown storage class!"); 1189 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1190 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1191 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1192 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1193 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1194 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1195 case DeclSpec::SCS_mutable: 1196 // mutable can only appear on non-static class members, so it's always 1197 // an error here 1198 Diag(Record->getLocation(), diag::err_mutable_nonmember); 1199 Invalid = true; 1200 SC = VarDecl::None; 1201 break; 1202 } 1203 1204 Anon = VarDecl::Create(Context, Owner, Record->getLocation(), 1205 /*IdentifierInfo=*/0, 1206 Context.getTypeDeclType(Record), 1207 SC, DS.getSourceRange().getBegin()); 1208 } 1209 Anon->setImplicit(); 1210 1211 // Add the anonymous struct/union object to the current 1212 // context. We'll be referencing this object when we refer to one of 1213 // its members. 1214 Owner->addDecl(Context, Anon); 1215 1216 // Inject the members of the anonymous struct/union into the owning 1217 // context and into the identifier resolver chain for name lookup 1218 // purposes. 1219 if (InjectAnonymousStructOrUnionMembers(S, Owner, Record)) 1220 Invalid = true; 1221 1222 // Mark this as an anonymous struct/union type. Note that we do not 1223 // do this until after we have already checked and injected the 1224 // members of this anonymous struct/union type, because otherwise 1225 // the members could be injected twice: once by DeclContext when it 1226 // builds its lookup table, and once by 1227 // InjectAnonymousStructOrUnionMembers. 1228 Record->setAnonymousStructOrUnion(true); 1229 1230 if (Invalid) 1231 Anon->setInvalidDecl(); 1232 1233 return DeclPtrTy::make(Anon); 1234} 1235 1236 1237/// GetNameForDeclarator - Determine the full declaration name for the 1238/// given Declarator. 1239DeclarationName Sema::GetNameForDeclarator(Declarator &D) { 1240 switch (D.getKind()) { 1241 case Declarator::DK_Abstract: 1242 assert(D.getIdentifier() == 0 && "abstract declarators have no name"); 1243 return DeclarationName(); 1244 1245 case Declarator::DK_Normal: 1246 assert (D.getIdentifier() != 0 && "normal declarators have an identifier"); 1247 return DeclarationName(D.getIdentifier()); 1248 1249 case Declarator::DK_Constructor: { 1250 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1251 Ty = Context.getCanonicalType(Ty); 1252 return Context.DeclarationNames.getCXXConstructorName(Ty); 1253 } 1254 1255 case Declarator::DK_Destructor: { 1256 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1257 Ty = Context.getCanonicalType(Ty); 1258 return Context.DeclarationNames.getCXXDestructorName(Ty); 1259 } 1260 1261 case Declarator::DK_Conversion: { 1262 // FIXME: We'd like to keep the non-canonical type for diagnostics! 1263 QualType Ty = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1264 Ty = Context.getCanonicalType(Ty); 1265 return Context.DeclarationNames.getCXXConversionFunctionName(Ty); 1266 } 1267 1268 case Declarator::DK_Operator: 1269 assert(D.getIdentifier() == 0 && "operator names have no identifier"); 1270 return Context.DeclarationNames.getCXXOperatorName( 1271 D.getOverloadedOperator()); 1272 } 1273 1274 assert(false && "Unknown name kind"); 1275 return DeclarationName(); 1276} 1277 1278/// isNearlyMatchingFunction - Determine whether the C++ functions 1279/// Declaration and Definition are "nearly" matching. This heuristic 1280/// is used to improve diagnostics in the case where an out-of-line 1281/// function definition doesn't match any declaration within 1282/// the class or namespace. 1283static bool isNearlyMatchingFunction(ASTContext &Context, 1284 FunctionDecl *Declaration, 1285 FunctionDecl *Definition) { 1286 if (Declaration->param_size() != Definition->param_size()) 1287 return false; 1288 for (unsigned Idx = 0; Idx < Declaration->param_size(); ++Idx) { 1289 QualType DeclParamTy = Declaration->getParamDecl(Idx)->getType(); 1290 QualType DefParamTy = Definition->getParamDecl(Idx)->getType(); 1291 1292 DeclParamTy = Context.getCanonicalType(DeclParamTy.getNonReferenceType()); 1293 DefParamTy = Context.getCanonicalType(DefParamTy.getNonReferenceType()); 1294 if (DeclParamTy.getUnqualifiedType() != DefParamTy.getUnqualifiedType()) 1295 return false; 1296 } 1297 1298 return true; 1299} 1300 1301Sema::DeclPtrTy 1302Sema::ActOnDeclarator(Scope *S, Declarator &D, bool IsFunctionDefinition) { 1303 DeclarationName Name = GetNameForDeclarator(D); 1304 1305 // All of these full declarators require an identifier. If it doesn't have 1306 // one, the ParsedFreeStandingDeclSpec action should be used. 1307 if (!Name) { 1308 if (!D.getInvalidType()) // Reject this if we think it is valid. 1309 Diag(D.getDeclSpec().getSourceRange().getBegin(), 1310 diag::err_declarator_need_ident) 1311 << D.getDeclSpec().getSourceRange() << D.getSourceRange(); 1312 return DeclPtrTy(); 1313 } 1314 1315 // The scope passed in may not be a decl scope. Zip up the scope tree until 1316 // we find one that is. 1317 while ((S->getFlags() & Scope::DeclScope) == 0 || 1318 (S->getFlags() & Scope::TemplateParamScope) != 0) 1319 S = S->getParent(); 1320 1321 DeclContext *DC; 1322 NamedDecl *PrevDecl; 1323 NamedDecl *New; 1324 bool InvalidDecl = false; 1325 1326 QualType R = GetTypeForDeclarator(D, S); 1327 if (R.isNull()) { 1328 InvalidDecl = true; 1329 R = Context.IntTy; 1330 } 1331 1332 // See if this is a redefinition of a variable in the same scope. 1333 if (D.getCXXScopeSpec().isInvalid()) { 1334 DC = CurContext; 1335 PrevDecl = 0; 1336 InvalidDecl = true; 1337 } else if (!D.getCXXScopeSpec().isSet()) { 1338 LookupNameKind NameKind = LookupOrdinaryName; 1339 1340 // If the declaration we're planning to build will be a function 1341 // or object with linkage, then look for another declaration with 1342 // linkage (C99 6.2.2p4-5 and C++ [basic.link]p6). 1343 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) 1344 /* Do nothing*/; 1345 else if (R->isFunctionType()) { 1346 if (CurContext->isFunctionOrMethod()) 1347 NameKind = LookupRedeclarationWithLinkage; 1348 } else if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_extern) 1349 NameKind = LookupRedeclarationWithLinkage; 1350 1351 DC = CurContext; 1352 PrevDecl = LookupName(S, Name, NameKind, true, 1353 D.getDeclSpec().getStorageClassSpec() != 1354 DeclSpec::SCS_static, 1355 D.getIdentifierLoc()); 1356 } else { // Something like "int foo::x;" 1357 DC = computeDeclContext(D.getCXXScopeSpec()); 1358 // FIXME: RequireCompleteDeclContext(D.getCXXScopeSpec()); ? 1359 PrevDecl = LookupQualifiedName(DC, Name, LookupOrdinaryName, true); 1360 1361 // C++ 7.3.1.2p2: 1362 // Members (including explicit specializations of templates) of a named 1363 // namespace can also be defined outside that namespace by explicit 1364 // qualification of the name being defined, provided that the entity being 1365 // defined was already declared in the namespace and the definition appears 1366 // after the point of declaration in a namespace that encloses the 1367 // declarations namespace. 1368 // 1369 // Note that we only check the context at this point. We don't yet 1370 // have enough information to make sure that PrevDecl is actually 1371 // the declaration we want to match. For example, given: 1372 // 1373 // class X { 1374 // void f(); 1375 // void f(float); 1376 // }; 1377 // 1378 // void X::f(int) { } // ill-formed 1379 // 1380 // In this case, PrevDecl will point to the overload set 1381 // containing the two f's declared in X, but neither of them 1382 // matches. 1383 1384 // First check whether we named the global scope. 1385 if (isa<TranslationUnitDecl>(DC)) { 1386 Diag(D.getIdentifierLoc(), diag::err_invalid_declarator_global_scope) 1387 << Name << D.getCXXScopeSpec().getRange(); 1388 } else if (!CurContext->Encloses(DC)) { 1389 // The qualifying scope doesn't enclose the original declaration. 1390 // Emit diagnostic based on current scope. 1391 SourceLocation L = D.getIdentifierLoc(); 1392 SourceRange R = D.getCXXScopeSpec().getRange(); 1393 if (isa<FunctionDecl>(CurContext)) 1394 Diag(L, diag::err_invalid_declarator_in_function) << Name << R; 1395 else 1396 Diag(L, diag::err_invalid_declarator_scope) 1397 << Name << cast<NamedDecl>(DC) << R; 1398 InvalidDecl = true; 1399 } 1400 } 1401 1402 if (PrevDecl && PrevDecl->isTemplateParameter()) { 1403 // Maybe we will complain about the shadowed template parameter. 1404 InvalidDecl = InvalidDecl 1405 || DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 1406 // Just pretend that we didn't see the previous declaration. 1407 PrevDecl = 0; 1408 } 1409 1410 // In C++, the previous declaration we find might be a tag type 1411 // (class or enum). In this case, the new declaration will hide the 1412 // tag type. Note that this does does not apply if we're declaring a 1413 // typedef (C++ [dcl.typedef]p4). 1414 if (PrevDecl && PrevDecl->getIdentifierNamespace() == Decl::IDNS_Tag && 1415 D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef) 1416 PrevDecl = 0; 1417 1418 bool Redeclaration = false; 1419 if (D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_typedef) { 1420 New = ActOnTypedefDeclarator(S, D, DC, R, PrevDecl, 1421 InvalidDecl, Redeclaration); 1422 } else if (R->isFunctionType()) { 1423 New = ActOnFunctionDeclarator(S, D, DC, R, PrevDecl, 1424 IsFunctionDefinition, InvalidDecl, 1425 Redeclaration); 1426 } else { 1427 New = ActOnVariableDeclarator(S, D, DC, R, PrevDecl, 1428 InvalidDecl, Redeclaration); 1429 } 1430 1431 if (New == 0) 1432 return DeclPtrTy(); 1433 1434 // If this has an identifier and is not an invalid redeclaration, 1435 // add it to the scope stack. 1436 if (Name && !(Redeclaration && InvalidDecl)) 1437 PushOnScopeChains(New, S); 1438 // If any semantic error occurred, mark the decl as invalid. 1439 if (D.getInvalidType() || InvalidDecl) 1440 New->setInvalidDecl(); 1441 1442 return DeclPtrTy::make(New); 1443} 1444 1445/// TryToFixInvalidVariablyModifiedType - Helper method to turn variable array 1446/// types into constant array types in certain situations which would otherwise 1447/// be errors (for GCC compatibility). 1448static QualType TryToFixInvalidVariablyModifiedType(QualType T, 1449 ASTContext &Context, 1450 bool &SizeIsNegative) { 1451 // This method tries to turn a variable array into a constant 1452 // array even when the size isn't an ICE. This is necessary 1453 // for compatibility with code that depends on gcc's buggy 1454 // constant expression folding, like struct {char x[(int)(char*)2];} 1455 SizeIsNegative = false; 1456 1457 if (const PointerType* PTy = dyn_cast<PointerType>(T)) { 1458 QualType Pointee = PTy->getPointeeType(); 1459 QualType FixedType = 1460 TryToFixInvalidVariablyModifiedType(Pointee, Context, SizeIsNegative); 1461 if (FixedType.isNull()) return FixedType; 1462 FixedType = Context.getPointerType(FixedType); 1463 FixedType.setCVRQualifiers(T.getCVRQualifiers()); 1464 return FixedType; 1465 } 1466 1467 const VariableArrayType* VLATy = dyn_cast<VariableArrayType>(T); 1468 if (!VLATy) 1469 return QualType(); 1470 // FIXME: We should probably handle this case 1471 if (VLATy->getElementType()->isVariablyModifiedType()) 1472 return QualType(); 1473 1474 Expr::EvalResult EvalResult; 1475 if (!VLATy->getSizeExpr() || 1476 !VLATy->getSizeExpr()->Evaluate(EvalResult, Context) || 1477 !EvalResult.Val.isInt()) 1478 return QualType(); 1479 1480 llvm::APSInt &Res = EvalResult.Val.getInt(); 1481 if (Res >= llvm::APSInt(Res.getBitWidth(), Res.isUnsigned())) 1482 return Context.getConstantArrayType(VLATy->getElementType(), 1483 Res, ArrayType::Normal, 0); 1484 1485 SizeIsNegative = true; 1486 return QualType(); 1487} 1488 1489/// \brief Register the given locally-scoped external C declaration so 1490/// that it can be found later for redeclarations 1491void 1492Sema::RegisterLocallyScopedExternCDecl(NamedDecl *ND, NamedDecl *PrevDecl, 1493 Scope *S) { 1494 assert(ND->getLexicalDeclContext()->isFunctionOrMethod() && 1495 "Decl is not a locally-scoped decl!"); 1496 // Note that we have a locally-scoped external with this name. 1497 LocallyScopedExternalDecls[ND->getDeclName()] = ND; 1498 1499 if (!PrevDecl) 1500 return; 1501 1502 // If there was a previous declaration of this variable, it may be 1503 // in our identifier chain. Update the identifier chain with the new 1504 // declaration. 1505 if (S && IdResolver.ReplaceDecl(PrevDecl, ND)) { 1506 // The previous declaration was found on the identifer resolver 1507 // chain, so remove it from its scope. 1508 while (S && !S->isDeclScope(DeclPtrTy::make(PrevDecl))) 1509 S = S->getParent(); 1510 1511 if (S) 1512 S->RemoveDecl(DeclPtrTy::make(PrevDecl)); 1513 } 1514} 1515 1516/// \brief Diagnose function specifiers on a declaration of an identifier that 1517/// does not identify a function. 1518void Sema::DiagnoseFunctionSpecifiers(Declarator& D) { 1519 // FIXME: We should probably indicate the identifier in question to avoid 1520 // confusion for constructs like "inline int a(), b;" 1521 if (D.getDeclSpec().isInlineSpecified()) 1522 Diag(D.getDeclSpec().getInlineSpecLoc(), 1523 diag::err_inline_non_function); 1524 1525 if (D.getDeclSpec().isVirtualSpecified()) 1526 Diag(D.getDeclSpec().getVirtualSpecLoc(), 1527 diag::err_virtual_non_function); 1528 1529 if (D.getDeclSpec().isExplicitSpecified()) 1530 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1531 diag::err_explicit_non_function); 1532} 1533 1534NamedDecl* 1535Sema::ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1536 QualType R, Decl* PrevDecl, bool& InvalidDecl, 1537 bool &Redeclaration) { 1538 // Typedef declarators cannot be qualified (C++ [dcl.meaning]p1). 1539 if (D.getCXXScopeSpec().isSet()) { 1540 Diag(D.getIdentifierLoc(), diag::err_qualified_typedef_declarator) 1541 << D.getCXXScopeSpec().getRange(); 1542 InvalidDecl = true; 1543 // Pretend we didn't see the scope specifier. 1544 DC = 0; 1545 } 1546 1547 if (getLangOptions().CPlusPlus) { 1548 // Check that there are no default arguments (C++ only). 1549 CheckExtraCXXDefaultArguments(D); 1550 } 1551 1552 DiagnoseFunctionSpecifiers(D); 1553 1554 TypedefDecl *NewTD = ParseTypedefDecl(S, D, R); 1555 if (!NewTD) return 0; 1556 1557 // Handle attributes prior to checking for duplicates in MergeVarDecl 1558 ProcessDeclAttributes(NewTD, D); 1559 // Merge the decl with the existing one if appropriate. If the decl is 1560 // in an outer scope, it isn't the same thing. 1561 if (PrevDecl && isDeclInScope(PrevDecl, DC, S)) { 1562 Redeclaration = true; 1563 if (MergeTypeDefDecl(NewTD, PrevDecl)) 1564 InvalidDecl = true; 1565 } 1566 1567 if (S->getFnParent() == 0) { 1568 QualType T = NewTD->getUnderlyingType(); 1569 // C99 6.7.7p2: If a typedef name specifies a variably modified type 1570 // then it shall have block scope. 1571 if (T->isVariablyModifiedType()) { 1572 bool SizeIsNegative; 1573 QualType FixedTy = 1574 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1575 if (!FixedTy.isNull()) { 1576 Diag(D.getIdentifierLoc(), diag::warn_illegal_constant_array_size); 1577 NewTD->setUnderlyingType(FixedTy); 1578 } else { 1579 if (SizeIsNegative) 1580 Diag(D.getIdentifierLoc(), diag::err_typecheck_negative_array_size); 1581 else if (T->isVariableArrayType()) 1582 Diag(D.getIdentifierLoc(), diag::err_vla_decl_in_file_scope); 1583 else 1584 Diag(D.getIdentifierLoc(), diag::err_vm_decl_in_file_scope); 1585 InvalidDecl = true; 1586 } 1587 } 1588 } 1589 return NewTD; 1590} 1591 1592/// \brief Determines whether the given declaration is an out-of-scope 1593/// previous declaration. 1594/// 1595/// This routine should be invoked when name lookup has found a 1596/// previous declaration (PrevDecl) that is not in the scope where a 1597/// new declaration by the same name is being introduced. If the new 1598/// declaration occurs in a local scope, previous declarations with 1599/// linkage may still be considered previous declarations (C99 1600/// 6.2.2p4-5, C++ [basic.link]p6). 1601/// 1602/// \param PrevDecl the previous declaration found by name 1603/// lookup 1604/// 1605/// \param DC the context in which the new declaration is being 1606/// declared. 1607/// 1608/// \returns true if PrevDecl is an out-of-scope previous declaration 1609/// for a new delcaration with the same name. 1610static bool 1611isOutOfScopePreviousDeclaration(NamedDecl *PrevDecl, DeclContext *DC, 1612 ASTContext &Context) { 1613 if (!PrevDecl) 1614 return 0; 1615 1616 // FIXME: PrevDecl could be an OverloadedFunctionDecl, in which 1617 // case we need to check each of the overloaded functions. 1618 if (!PrevDecl->hasLinkage()) 1619 return false; 1620 1621 if (Context.getLangOptions().CPlusPlus) { 1622 // C++ [basic.link]p6: 1623 // If there is a visible declaration of an entity with linkage 1624 // having the same name and type, ignoring entities declared 1625 // outside the innermost enclosing namespace scope, the block 1626 // scope declaration declares that same entity and receives the 1627 // linkage of the previous declaration. 1628 DeclContext *OuterContext = DC->getLookupContext(); 1629 if (!OuterContext->isFunctionOrMethod()) 1630 // This rule only applies to block-scope declarations. 1631 return false; 1632 else { 1633 DeclContext *PrevOuterContext = PrevDecl->getDeclContext(); 1634 if (PrevOuterContext->isRecord()) 1635 // We found a member function: ignore it. 1636 return false; 1637 else { 1638 // Find the innermost enclosing namespace for the new and 1639 // previous declarations. 1640 while (!OuterContext->isFileContext()) 1641 OuterContext = OuterContext->getParent(); 1642 while (!PrevOuterContext->isFileContext()) 1643 PrevOuterContext = PrevOuterContext->getParent(); 1644 1645 // The previous declaration is in a different namespace, so it 1646 // isn't the same function. 1647 if (OuterContext->getPrimaryContext() != 1648 PrevOuterContext->getPrimaryContext()) 1649 return false; 1650 } 1651 } 1652 } 1653 1654 return true; 1655} 1656 1657NamedDecl* 1658Sema::ActOnVariableDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1659 QualType R,NamedDecl* PrevDecl, bool& InvalidDecl, 1660 bool &Redeclaration) { 1661 DeclarationName Name = GetNameForDeclarator(D); 1662 1663 // Check that there are no default arguments (C++ only). 1664 if (getLangOptions().CPlusPlus) 1665 CheckExtraCXXDefaultArguments(D); 1666 1667 VarDecl *NewVD; 1668 VarDecl::StorageClass SC; 1669 switch (D.getDeclSpec().getStorageClassSpec()) { 1670 default: assert(0 && "Unknown storage class!"); 1671 case DeclSpec::SCS_unspecified: SC = VarDecl::None; break; 1672 case DeclSpec::SCS_extern: SC = VarDecl::Extern; break; 1673 case DeclSpec::SCS_static: SC = VarDecl::Static; break; 1674 case DeclSpec::SCS_auto: SC = VarDecl::Auto; break; 1675 case DeclSpec::SCS_register: SC = VarDecl::Register; break; 1676 case DeclSpec::SCS_private_extern: SC = VarDecl::PrivateExtern; break; 1677 case DeclSpec::SCS_mutable: 1678 // mutable can only appear on non-static class members, so it's always 1679 // an error here 1680 Diag(D.getIdentifierLoc(), diag::err_mutable_nonmember); 1681 InvalidDecl = true; 1682 SC = VarDecl::None; 1683 break; 1684 } 1685 1686 IdentifierInfo *II = Name.getAsIdentifierInfo(); 1687 if (!II) { 1688 Diag(D.getIdentifierLoc(), diag::err_bad_variable_name) 1689 << Name.getAsString(); 1690 return 0; 1691 } 1692 1693 DiagnoseFunctionSpecifiers(D); 1694 1695 bool ThreadSpecified = D.getDeclSpec().isThreadSpecified(); 1696 if (!DC->isRecord() && S->getFnParent() == 0) { 1697 // C99 6.9p2: The storage-class specifiers auto and register shall not 1698 // appear in the declaration specifiers in an external declaration. 1699 if (SC == VarDecl::Auto || SC == VarDecl::Register) { 1700 Diag(D.getIdentifierLoc(), diag::err_typecheck_sclass_fscope); 1701 InvalidDecl = true; 1702 } 1703 } 1704 if (DC->isRecord() && !CurContext->isRecord()) { 1705 // This is an out-of-line definition of a static data member. 1706 if (SC == VarDecl::Static) { 1707 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1708 diag::err_static_out_of_line) 1709 << CodeModificationHint::CreateRemoval( 1710 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 1711 } else if (SC == VarDecl::None) 1712 SC = VarDecl::Static; 1713 } 1714 1715 // The variable can not 1716 NewVD = VarDecl::Create(Context, DC, D.getIdentifierLoc(), 1717 II, R, SC, 1718 // FIXME: Move to DeclGroup... 1719 D.getDeclSpec().getSourceRange().getBegin()); 1720 NewVD->setThreadSpecified(ThreadSpecified); 1721 1722 // Set the lexical context. If the declarator has a C++ scope specifier, the 1723 // lexical context will be different from the semantic context. 1724 NewVD->setLexicalDeclContext(CurContext); 1725 1726 // Handle attributes prior to checking for duplicates in MergeVarDecl 1727 ProcessDeclAttributes(NewVD, D); 1728 1729 // Handle GNU asm-label extension (encoded as an attribute). 1730 if (Expr *E = (Expr*) D.getAsmLabel()) { 1731 // The parser guarantees this is a string. 1732 StringLiteral *SE = cast<StringLiteral>(E); 1733 NewVD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 1734 SE->getByteLength()))); 1735 } 1736 1737 // If name lookup finds a previous declaration that is not in the 1738 // same scope as the new declaration, this may still be an 1739 // acceptable redeclaration. 1740 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 1741 !(NewVD->hasLinkage() && 1742 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 1743 PrevDecl = 0; 1744 1745 // Merge the decl with the existing one if appropriate. 1746 if (PrevDecl) { 1747 if (isa<FieldDecl>(PrevDecl) && D.getCXXScopeSpec().isSet()) { 1748 // The user tried to define a non-static data member 1749 // out-of-line (C++ [dcl.meaning]p1). 1750 Diag(NewVD->getLocation(), diag::err_nonstatic_member_out_of_line) 1751 << D.getCXXScopeSpec().getRange(); 1752 PrevDecl = 0; 1753 InvalidDecl = true; 1754 } 1755 } else if (D.getCXXScopeSpec().isSet()) { 1756 // No previous declaration in the qualifying scope. 1757 Diag(D.getIdentifierLoc(), diag::err_typecheck_no_member) 1758 << Name << D.getCXXScopeSpec().getRange(); 1759 InvalidDecl = true; 1760 } 1761 1762 if (CheckVariableDeclaration(NewVD, PrevDecl, Redeclaration)) 1763 InvalidDecl = true; 1764 1765 // If this is a locally-scoped extern C variable, update the map of 1766 // such variables. 1767 if (CurContext->isFunctionOrMethod() && NewVD->isExternC(Context) && 1768 !InvalidDecl) 1769 RegisterLocallyScopedExternCDecl(NewVD, PrevDecl, S); 1770 1771 return NewVD; 1772} 1773 1774/// \brief Perform semantic checking on a newly-created variable 1775/// declaration. 1776/// 1777/// This routine performs all of the type-checking required for a 1778/// variable declaration once it has been build. It is used both to 1779/// check variables after they have been parsed and their declarators 1780/// have been translated into a declaration, and to check 1781/// 1782/// \returns true if an error was encountered, false otherwise. 1783bool Sema::CheckVariableDeclaration(VarDecl *NewVD, NamedDecl *PrevDecl, 1784 bool &Redeclaration) { 1785 bool Invalid = false; 1786 1787 QualType T = NewVD->getType(); 1788 1789 if (T->isObjCInterfaceType()) { 1790 Diag(NewVD->getLocation(), diag::err_statically_allocated_object); 1791 Invalid = true; 1792 } 1793 1794 // The variable can not have an abstract class type. 1795 if (RequireNonAbstractType(NewVD->getLocation(), T, 1796 diag::err_abstract_type_in_decl, 1797 AbstractVariableType)) 1798 Invalid = true; 1799 1800 // Emit an error if an address space was applied to decl with local storage. 1801 // This includes arrays of objects with address space qualifiers, but not 1802 // automatic variables that point to other address spaces. 1803 // ISO/IEC TR 18037 S5.1.2 1804 if (NewVD->hasLocalStorage() && (T.getAddressSpace() != 0)) { 1805 Diag(NewVD->getLocation(), diag::err_as_qualified_auto_decl); 1806 Invalid = true; 1807 } 1808 1809 if (NewVD->hasLocalStorage() && T.isObjCGCWeak() 1810 && !NewVD->hasAttr<BlocksAttr>()) 1811 Diag(NewVD->getLocation(), diag::warn_attribute_weak_on_local); 1812 1813 bool isIllegalVLA = T->isVariableArrayType() && NewVD->hasGlobalStorage(); 1814 bool isIllegalVM = T->isVariablyModifiedType() && NewVD->hasLinkage(); 1815 if (isIllegalVLA || isIllegalVM) { 1816 bool SizeIsNegative; 1817 QualType FixedTy = 1818 TryToFixInvalidVariablyModifiedType(T, Context, SizeIsNegative); 1819 if (!FixedTy.isNull()) { 1820 Diag(NewVD->getLocation(), diag::warn_illegal_constant_array_size); 1821 NewVD->setType(FixedTy); 1822 } else if (T->isVariableArrayType()) { 1823 Invalid = true; 1824 1825 const VariableArrayType *VAT = Context.getAsVariableArrayType(T); 1826 // FIXME: This won't give the correct result for 1827 // int a[10][n]; 1828 SourceRange SizeRange = VAT->getSizeExpr()->getSourceRange(); 1829 1830 if (NewVD->isFileVarDecl()) 1831 Diag(NewVD->getLocation(), diag::err_vla_decl_in_file_scope) 1832 << SizeRange; 1833 else if (NewVD->getStorageClass() == VarDecl::Static) 1834 Diag(NewVD->getLocation(), diag::err_vla_decl_has_static_storage) 1835 << SizeRange; 1836 else 1837 Diag(NewVD->getLocation(), diag::err_vla_decl_has_extern_linkage) 1838 << SizeRange; 1839 } else { 1840 Invalid = true; 1841 1842 if (NewVD->isFileVarDecl()) 1843 Diag(NewVD->getLocation(), diag::err_vm_decl_in_file_scope); 1844 else 1845 Diag(NewVD->getLocation(), diag::err_vm_decl_has_extern_linkage); 1846 } 1847 } 1848 1849 if (!PrevDecl && NewVD->isExternC(Context)) { 1850 // Since we did not find anything by this name and we're declaring 1851 // an extern "C" variable, look for a non-visible extern "C" 1852 // declaration with the same name. 1853 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 1854 = LocallyScopedExternalDecls.find(NewVD->getDeclName()); 1855 if (Pos != LocallyScopedExternalDecls.end()) 1856 PrevDecl = Pos->second; 1857 } 1858 1859 if (!Invalid && T->isVoidType() && !NewVD->hasExternalStorage()) { 1860 Diag(NewVD->getLocation(), diag::err_typecheck_decl_incomplete_type) 1861 << T; 1862 Invalid = true; 1863 } 1864 1865 if (PrevDecl) { 1866 Redeclaration = true; 1867 if (MergeVarDecl(NewVD, PrevDecl)) 1868 Invalid = true; 1869 } 1870 1871 return NewVD->isInvalidDecl() || Invalid; 1872} 1873 1874NamedDecl* 1875Sema::ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC, 1876 QualType R, NamedDecl* PrevDecl, 1877 bool IsFunctionDefinition, 1878 bool& InvalidDecl, bool &Redeclaration) { 1879 assert(R.getTypePtr()->isFunctionType()); 1880 1881 DeclarationName Name = GetNameForDeclarator(D); 1882 FunctionDecl::StorageClass SC = FunctionDecl::None; 1883 switch (D.getDeclSpec().getStorageClassSpec()) { 1884 default: assert(0 && "Unknown storage class!"); 1885 case DeclSpec::SCS_auto: 1886 case DeclSpec::SCS_register: 1887 case DeclSpec::SCS_mutable: 1888 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1889 diag::err_typecheck_sclass_func); 1890 InvalidDecl = true; 1891 break; 1892 case DeclSpec::SCS_unspecified: SC = FunctionDecl::None; break; 1893 case DeclSpec::SCS_extern: SC = FunctionDecl::Extern; break; 1894 case DeclSpec::SCS_static: { 1895 if (CurContext->getLookupContext()->isFunctionOrMethod()) { 1896 // C99 6.7.1p5: 1897 // The declaration of an identifier for a function that has 1898 // block scope shall have no explicit storage-class specifier 1899 // other than extern 1900 // See also (C++ [dcl.stc]p4). 1901 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 1902 diag::err_static_block_func); 1903 SC = FunctionDecl::None; 1904 } else 1905 SC = FunctionDecl::Static; 1906 break; 1907 } 1908 case DeclSpec::SCS_private_extern: SC = FunctionDecl::PrivateExtern;break; 1909 } 1910 1911 bool isInline = D.getDeclSpec().isInlineSpecified(); 1912 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1913 bool isExplicit = D.getDeclSpec().isExplicitSpecified(); 1914 1915 // Check that the return type is not an abstract class type. 1916 // For record types, this is done by the AbstractClassUsageDiagnoser once 1917 // the class has been completely parsed. 1918 if (!DC->isRecord() && 1919 RequireNonAbstractType(D.getIdentifierLoc(), 1920 R->getAsFunctionType()->getResultType(), 1921 diag::err_abstract_type_in_decl, 1922 AbstractReturnType)) 1923 InvalidDecl = true; 1924 1925 // Do not allow returning a objc interface by-value. 1926 if (R->getAsFunctionType()->getResultType()->isObjCInterfaceType()) { 1927 Diag(D.getIdentifierLoc(), 1928 diag::err_object_cannot_be_passed_returned_by_value) << 0 1929 << R->getAsFunctionType()->getResultType(); 1930 InvalidDecl = true; 1931 } 1932 1933 bool isVirtualOkay = false; 1934 FunctionDecl *NewFD; 1935 if (D.getKind() == Declarator::DK_Constructor) { 1936 // This is a C++ constructor declaration. 1937 assert(DC->isRecord() && 1938 "Constructors can only be declared in a member context"); 1939 1940 InvalidDecl = InvalidDecl || CheckConstructorDeclarator(D, R, SC); 1941 1942 // Create the new declaration 1943 NewFD = CXXConstructorDecl::Create(Context, 1944 cast<CXXRecordDecl>(DC), 1945 D.getIdentifierLoc(), Name, R, 1946 isExplicit, isInline, 1947 /*isImplicitlyDeclared=*/false); 1948 1949 if (InvalidDecl) 1950 NewFD->setInvalidDecl(); 1951 } else if (D.getKind() == Declarator::DK_Destructor) { 1952 // This is a C++ destructor declaration. 1953 if (DC->isRecord()) { 1954 InvalidDecl = InvalidDecl || CheckDestructorDeclarator(D, R, SC); 1955 1956 NewFD = CXXDestructorDecl::Create(Context, 1957 cast<CXXRecordDecl>(DC), 1958 D.getIdentifierLoc(), Name, R, 1959 isInline, 1960 /*isImplicitlyDeclared=*/false); 1961 1962 if (InvalidDecl) 1963 NewFD->setInvalidDecl(); 1964 1965 isVirtualOkay = true; 1966 } else { 1967 Diag(D.getIdentifierLoc(), diag::err_destructor_not_member); 1968 1969 // Create a FunctionDecl to satisfy the function definition parsing 1970 // code path. 1971 NewFD = FunctionDecl::Create(Context, DC, D.getIdentifierLoc(), 1972 Name, R, SC, isInline, 1973 /*hasPrototype=*/true, 1974 // FIXME: Move to DeclGroup... 1975 D.getDeclSpec().getSourceRange().getBegin()); 1976 InvalidDecl = true; 1977 NewFD->setInvalidDecl(); 1978 } 1979 } else if (D.getKind() == Declarator::DK_Conversion) { 1980 if (!DC->isRecord()) { 1981 Diag(D.getIdentifierLoc(), 1982 diag::err_conv_function_not_member); 1983 return 0; 1984 } else { 1985 InvalidDecl = InvalidDecl || CheckConversionDeclarator(D, R, SC); 1986 1987 NewFD = CXXConversionDecl::Create(Context, cast<CXXRecordDecl>(DC), 1988 D.getIdentifierLoc(), Name, R, 1989 isInline, isExplicit); 1990 1991 if (InvalidDecl) 1992 NewFD->setInvalidDecl(); 1993 1994 isVirtualOkay = true; 1995 } 1996 } else if (DC->isRecord()) { 1997 // This is a C++ method declaration. 1998 NewFD = CXXMethodDecl::Create(Context, cast<CXXRecordDecl>(DC), 1999 D.getIdentifierLoc(), Name, R, 2000 (SC == FunctionDecl::Static), isInline); 2001 2002 isVirtualOkay = (SC != FunctionDecl::Static); 2003 } else { 2004 // Determine whether the function was written with a 2005 // prototype. This true when: 2006 // - we're in C++ (where every function has a prototype), 2007 // - there is a prototype in the declarator, or 2008 // - the type R of the function is some kind of typedef or other reference 2009 // to a type name (which eventually refers to a function type). 2010 bool HasPrototype = 2011 getLangOptions().CPlusPlus || 2012 (D.getNumTypeObjects() && D.getTypeObject(0).Fun.hasPrototype) || 2013 (!isa<FunctionType>(R.getTypePtr()) && R->isFunctionProtoType()); 2014 2015 NewFD = FunctionDecl::Create(Context, DC, 2016 D.getIdentifierLoc(), 2017 Name, R, SC, isInline, HasPrototype, 2018 // FIXME: Move to DeclGroup... 2019 D.getDeclSpec().getSourceRange().getBegin()); 2020 } 2021 2022 // Set the lexical context. If the declarator has a C++ 2023 // scope specifier, the lexical context will be different 2024 // from the semantic context. 2025 NewFD->setLexicalDeclContext(CurContext); 2026 2027 // C++ [dcl.fct.spec]p5: 2028 // The virtual specifier shall only be used in declarations of 2029 // nonstatic class member functions that appear within a 2030 // member-specification of a class declaration; see 10.3. 2031 // 2032 // FIXME: Checking the 'virtual' specifier is not sufficient. A 2033 // function is also virtual if it overrides an already virtual 2034 // function. This is important to do here because it's part of the 2035 // declaration. 2036 if (isVirtual && !InvalidDecl) { 2037 if (!isVirtualOkay) { 2038 Diag(D.getDeclSpec().getVirtualSpecLoc(), 2039 diag::err_virtual_non_function); 2040 } else if (!CurContext->isRecord()) { 2041 // 'virtual' was specified outside of the class. 2042 Diag(D.getDeclSpec().getVirtualSpecLoc(), diag::err_virtual_out_of_class) 2043 << CodeModificationHint::CreateRemoval( 2044 SourceRange(D.getDeclSpec().getVirtualSpecLoc())); 2045 } else { 2046 // Okay: Add virtual to the method. 2047 cast<CXXMethodDecl>(NewFD)->setVirtual(); 2048 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(DC); 2049 CurClass->setAggregate(false); 2050 CurClass->setPOD(false); 2051 CurClass->setPolymorphic(true); 2052 CurClass->setHasTrivialConstructor(false); 2053 } 2054 } 2055 2056 if (SC == FunctionDecl::Static && isa<CXXMethodDecl>(NewFD) && 2057 !CurContext->isRecord()) { 2058 // C++ [class.static]p1: 2059 // A data or function member of a class may be declared static 2060 // in a class definition, in which case it is a static member of 2061 // the class. 2062 2063 // Complain about the 'static' specifier if it's on an out-of-line 2064 // member function definition. 2065 Diag(D.getDeclSpec().getStorageClassSpecLoc(), 2066 diag::err_static_out_of_line) 2067 << CodeModificationHint::CreateRemoval( 2068 SourceRange(D.getDeclSpec().getStorageClassSpecLoc())); 2069 } 2070 2071 // Handle GNU asm-label extension (encoded as an attribute). 2072 if (Expr *E = (Expr*) D.getAsmLabel()) { 2073 // The parser guarantees this is a string. 2074 StringLiteral *SE = cast<StringLiteral>(E); 2075 NewFD->addAttr(::new (Context) AsmLabelAttr(std::string(SE->getStrData(), 2076 SE->getByteLength()))); 2077 } 2078 2079 // Copy the parameter declarations from the declarator D to 2080 // the function declaration NewFD, if they are available. 2081 if (D.getNumTypeObjects() > 0) { 2082 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2083 2084 // Create Decl objects for each parameter, adding them to the 2085 // FunctionDecl. 2086 llvm::SmallVector<ParmVarDecl*, 16> Params; 2087 2088 // Check for C99 6.7.5.3p10 - foo(void) is a non-varargs 2089 // function that takes no arguments, not a function that takes a 2090 // single void argument. 2091 // We let through "const void" here because Sema::GetTypeForDeclarator 2092 // already checks for that case. 2093 if (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 2094 FTI.ArgInfo[0].Param && 2095 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()) { 2096 // empty arg list, don't push any params. 2097 ParmVarDecl *Param = FTI.ArgInfo[0].Param.getAs<ParmVarDecl>(); 2098 2099 // In C++, the empty parameter-type-list must be spelled "void"; a 2100 // typedef of void is not permitted. 2101 if (getLangOptions().CPlusPlus && 2102 Param->getType().getUnqualifiedType() != Context.VoidTy) { 2103 Diag(Param->getLocation(), diag::err_param_typedef_of_void); 2104 } 2105 } else if (FTI.NumArgs > 0 && FTI.ArgInfo[0].Param != 0) { 2106 for (unsigned i = 0, e = FTI.NumArgs; i != e; ++i) 2107 Params.push_back(FTI.ArgInfo[i].Param.getAs<ParmVarDecl>()); 2108 } 2109 2110 NewFD->setParams(Context, &Params[0], Params.size()); 2111 } else if (R->getAsTypedefType()) { 2112 // When we're declaring a function with a typedef, as in the 2113 // following example, we'll need to synthesize (unnamed) 2114 // parameters for use in the declaration. 2115 // 2116 // @code 2117 // typedef void fn(int); 2118 // fn f; 2119 // @endcode 2120 const FunctionProtoType *FT = R->getAsFunctionProtoType(); 2121 if (!FT) { 2122 // This is a typedef of a function with no prototype, so we 2123 // don't need to do anything. 2124 } else if ((FT->getNumArgs() == 0) || 2125 (FT->getNumArgs() == 1 && !FT->isVariadic() && 2126 FT->getArgType(0)->isVoidType())) { 2127 // This is a zero-argument function. We don't need to do anything. 2128 } else { 2129 // Synthesize a parameter for each argument type. 2130 llvm::SmallVector<ParmVarDecl*, 16> Params; 2131 for (FunctionProtoType::arg_type_iterator ArgType = FT->arg_type_begin(); 2132 ArgType != FT->arg_type_end(); ++ArgType) { 2133 ParmVarDecl *Param = ParmVarDecl::Create(Context, DC, 2134 SourceLocation(), 0, 2135 *ArgType, VarDecl::None, 2136 0); 2137 Param->setImplicit(); 2138 Params.push_back(Param); 2139 } 2140 2141 NewFD->setParams(Context, &Params[0], Params.size()); 2142 } 2143 } 2144 2145 // If name lookup finds a previous declaration that is not in the 2146 // same scope as the new declaration, this may still be an 2147 // acceptable redeclaration. 2148 if (PrevDecl && !isDeclInScope(PrevDecl, DC, S) && 2149 !(NewFD->hasLinkage() && 2150 isOutOfScopePreviousDeclaration(PrevDecl, DC, Context))) 2151 PrevDecl = 0; 2152 2153 // Perform semantic checking on the function declaration. 2154 bool OverloadableAttrRequired = false; // FIXME: HACK! 2155 if (CheckFunctionDeclaration(NewFD, PrevDecl, Redeclaration, 2156 /*FIXME:*/OverloadableAttrRequired)) 2157 InvalidDecl = true; 2158 2159 if (D.getCXXScopeSpec().isSet() && !InvalidDecl) { 2160 // An out-of-line member function declaration must also be a 2161 // definition (C++ [dcl.meaning]p1). 2162 if (!IsFunctionDefinition) { 2163 Diag(NewFD->getLocation(), diag::err_out_of_line_declaration) 2164 << D.getCXXScopeSpec().getRange(); 2165 InvalidDecl = true; 2166 } else if (!Redeclaration) { 2167 // The user tried to provide an out-of-line definition for a 2168 // function that is a member of a class or namespace, but there 2169 // was no such member function declared (C++ [class.mfct]p2, 2170 // C++ [namespace.memdef]p2). For example: 2171 // 2172 // class X { 2173 // void f() const; 2174 // }; 2175 // 2176 // void X::f() { } // ill-formed 2177 // 2178 // Complain about this problem, and attempt to suggest close 2179 // matches (e.g., those that differ only in cv-qualifiers and 2180 // whether the parameter types are references). 2181 Diag(D.getIdentifierLoc(), diag::err_member_def_does_not_match) 2182 << cast<NamedDecl>(DC) << D.getCXXScopeSpec().getRange(); 2183 InvalidDecl = true; 2184 2185 LookupResult Prev = LookupQualifiedName(DC, Name, LookupOrdinaryName, 2186 true); 2187 assert(!Prev.isAmbiguous() && 2188 "Cannot have an ambiguity in previous-declaration lookup"); 2189 for (LookupResult::iterator Func = Prev.begin(), FuncEnd = Prev.end(); 2190 Func != FuncEnd; ++Func) { 2191 if (isa<FunctionDecl>(*Func) && 2192 isNearlyMatchingFunction(Context, cast<FunctionDecl>(*Func), NewFD)) 2193 Diag((*Func)->getLocation(), diag::note_member_def_close_match); 2194 } 2195 2196 PrevDecl = 0; 2197 } 2198 } 2199 2200 // Handle attributes. We need to have merged decls when handling attributes 2201 // (for example to check for conflicts, etc). 2202 // FIXME: This needs to happen before we merge declarations. Then, 2203 // let attribute merging cope with attribute conflicts. 2204 ProcessDeclAttributes(NewFD, D); 2205 AddKnownFunctionAttributes(NewFD); 2206 2207 if (OverloadableAttrRequired && !NewFD->getAttr<OverloadableAttr>()) { 2208 // If a function name is overloadable in C, then every function 2209 // with that name must be marked "overloadable". 2210 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_missing) 2211 << Redeclaration << NewFD; 2212 if (PrevDecl) 2213 Diag(PrevDecl->getLocation(), 2214 diag::note_attribute_overloadable_prev_overload); 2215 NewFD->addAttr(::new (Context) OverloadableAttr()); 2216 } 2217 2218 // If this is a locally-scoped extern C function, update the 2219 // map of such names. 2220 if (CurContext->isFunctionOrMethod() && NewFD->isExternC(Context) 2221 && !InvalidDecl) 2222 RegisterLocallyScopedExternCDecl(NewFD, PrevDecl, S); 2223 2224 return NewFD; 2225} 2226 2227/// \brief Perform semantic checking of a new function declaration. 2228/// 2229/// Performs semantic analysis of the new function declaration 2230/// NewFD. This routine performs all semantic checking that does not 2231/// require the actual declarator involved in the declaration, and is 2232/// used both for the declaration of functions as they are parsed 2233/// (called via ActOnDeclarator) and for the declaration of functions 2234/// that have been instantiated via C++ template instantiation (called 2235/// via InstantiateDecl). 2236/// 2237/// \returns true if there was an error, false otherwise. 2238bool Sema::CheckFunctionDeclaration(FunctionDecl *NewFD, NamedDecl *&PrevDecl, 2239 bool &Redeclaration, 2240 bool &OverloadableAttrRequired) { 2241 bool InvalidDecl = false; 2242 2243 // Semantic checking for this function declaration (in isolation). 2244 if (getLangOptions().CPlusPlus) { 2245 // C++-specific checks. 2246 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(NewFD)) 2247 InvalidDecl = InvalidDecl || CheckConstructor(Constructor); 2248 else if (isa<CXXDestructorDecl>(NewFD)) { 2249 CXXRecordDecl *Record = cast<CXXRecordDecl>(NewFD->getParent()); 2250 Record->setUserDeclaredDestructor(true); 2251 // C++ [class]p4: A POD-struct is an aggregate class that has [...] no 2252 // user-defined destructor. 2253 Record->setPOD(false); 2254 } else if (CXXConversionDecl *Conversion 2255 = dyn_cast<CXXConversionDecl>(NewFD)) 2256 ActOnConversionDeclarator(Conversion); 2257 2258 // Extra checking for C++ overloaded operators (C++ [over.oper]). 2259 if (NewFD->isOverloadedOperator() && 2260 CheckOverloadedOperatorDeclaration(NewFD)) 2261 InvalidDecl = true; 2262 } 2263 2264 // Check for a previous declaration of this name. 2265 if (!PrevDecl && NewFD->isExternC(Context)) { 2266 // Since we did not find anything by this name and we're declaring 2267 // an extern "C" function, look for a non-visible extern "C" 2268 // declaration with the same name. 2269 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 2270 = LocallyScopedExternalDecls.find(NewFD->getDeclName()); 2271 if (Pos != LocallyScopedExternalDecls.end()) 2272 PrevDecl = Pos->second; 2273 } 2274 2275 // Merge or overload the declaration with an existing declaration of 2276 // the same name, if appropriate. 2277 if (PrevDecl) { 2278 // Determine whether NewFD is an overload of PrevDecl or 2279 // a declaration that requires merging. If it's an overload, 2280 // there's no more work to do here; we'll just add the new 2281 // function to the scope. 2282 OverloadedFunctionDecl::function_iterator MatchedDecl; 2283 2284 if (!getLangOptions().CPlusPlus && 2285 AllowOverloadingOfFunction(PrevDecl, Context)) { 2286 OverloadableAttrRequired = true; 2287 2288 // Functions marked "overloadable" must have a prototype (that 2289 // we can't get through declaration merging). 2290 if (!NewFD->getType()->getAsFunctionProtoType()) { 2291 Diag(NewFD->getLocation(), diag::err_attribute_overloadable_no_prototype) 2292 << NewFD; 2293 InvalidDecl = true; 2294 Redeclaration = true; 2295 2296 // Turn this into a variadic function with no parameters. 2297 QualType R = Context.getFunctionType( 2298 NewFD->getType()->getAsFunctionType()->getResultType(), 2299 0, 0, true, 0); 2300 NewFD->setType(R); 2301 } 2302 } 2303 2304 if (PrevDecl && 2305 (!AllowOverloadingOfFunction(PrevDecl, Context) || 2306 !IsOverload(NewFD, PrevDecl, MatchedDecl))) { 2307 Redeclaration = true; 2308 Decl *OldDecl = PrevDecl; 2309 2310 // If PrevDecl was an overloaded function, extract the 2311 // FunctionDecl that matched. 2312 if (isa<OverloadedFunctionDecl>(PrevDecl)) 2313 OldDecl = *MatchedDecl; 2314 2315 // NewFD and OldDecl represent declarations that need to be 2316 // merged. 2317 if (MergeFunctionDecl(NewFD, OldDecl)) 2318 InvalidDecl = true; 2319 2320 if (!InvalidDecl) 2321 NewFD->setPreviousDeclaration(cast<FunctionDecl>(OldDecl)); 2322 } 2323 } 2324 2325 if (getLangOptions().CPlusPlus && !CurContext->isRecord()) { 2326 // In C++, check default arguments now that we have merged decls. Unless 2327 // the lexical context is the class, because in this case this is done 2328 // during delayed parsing anyway. 2329 CheckCXXDefaultArguments(NewFD); 2330 } 2331 2332 return InvalidDecl || NewFD->isInvalidDecl(); 2333} 2334 2335bool Sema::CheckForConstantInitializer(Expr *Init, QualType DclT) { 2336 // FIXME: Need strict checking. In C89, we need to check for 2337 // any assignment, increment, decrement, function-calls, or 2338 // commas outside of a sizeof. In C99, it's the same list, 2339 // except that the aforementioned are allowed in unevaluated 2340 // expressions. Everything else falls under the 2341 // "may accept other forms of constant expressions" exception. 2342 // (We never end up here for C++, so the constant expression 2343 // rules there don't matter.) 2344 if (Init->isConstantInitializer(Context)) 2345 return false; 2346 Diag(Init->getExprLoc(), diag::err_init_element_not_constant) 2347 << Init->getSourceRange(); 2348 return true; 2349} 2350 2351void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init) { 2352 AddInitializerToDecl(dcl, move(init), /*DirectInit=*/false); 2353} 2354 2355/// AddInitializerToDecl - Adds the initializer Init to the 2356/// declaration dcl. If DirectInit is true, this is C++ direct 2357/// initialization rather than copy initialization. 2358void Sema::AddInitializerToDecl(DeclPtrTy dcl, ExprArg init, bool DirectInit) { 2359 Decl *RealDecl = dcl.getAs<Decl>(); 2360 // If there is no declaration, there was an error parsing it. Just ignore 2361 // the initializer. 2362 if (RealDecl == 0) 2363 return; 2364 2365 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(RealDecl)) { 2366 // With declarators parsed the way they are, the parser cannot 2367 // distinguish between a normal initializer and a pure-specifier. 2368 // Thus this grotesque test. 2369 IntegerLiteral *IL; 2370 Expr *Init = static_cast<Expr *>(init.get()); 2371 if ((IL = dyn_cast<IntegerLiteral>(Init)) && IL->getValue() == 0 && 2372 Context.getCanonicalType(IL->getType()) == Context.IntTy) { 2373 if (Method->isVirtual()) { 2374 Method->setPure(); 2375 2376 // A class is abstract if at least one function is pure virtual. 2377 cast<CXXRecordDecl>(CurContext)->setAbstract(true); 2378 } else if (!Method->isInvalidDecl()) { 2379 Diag(Method->getLocation(), diag::err_non_virtual_pure) 2380 << Method->getDeclName() << Init->getSourceRange(); 2381 Method->setInvalidDecl(); 2382 } 2383 } else { 2384 Diag(Method->getLocation(), diag::err_member_function_initialization) 2385 << Method->getDeclName() << Init->getSourceRange(); 2386 Method->setInvalidDecl(); 2387 } 2388 return; 2389 } 2390 2391 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 2392 if (!VDecl) { 2393 if (getLangOptions().CPlusPlus && 2394 RealDecl->getLexicalDeclContext()->isRecord() && 2395 isa<NamedDecl>(RealDecl)) 2396 Diag(RealDecl->getLocation(), diag::err_member_initialization) 2397 << cast<NamedDecl>(RealDecl)->getDeclName(); 2398 else 2399 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 2400 RealDecl->setInvalidDecl(); 2401 return; 2402 } 2403 2404 if (!VDecl->getType()->isArrayType() && 2405 RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 2406 diag::err_typecheck_decl_incomplete_type)) { 2407 RealDecl->setInvalidDecl(); 2408 return; 2409 } 2410 2411 const VarDecl *Def = 0; 2412 if (VDecl->getDefinition(Def)) { 2413 Diag(VDecl->getLocation(), diag::err_redefinition) 2414 << VDecl->getDeclName(); 2415 Diag(Def->getLocation(), diag::note_previous_definition); 2416 VDecl->setInvalidDecl(); 2417 return; 2418 } 2419 2420 // Take ownership of the expression, now that we're sure we have somewhere 2421 // to put it. 2422 Expr *Init = static_cast<Expr *>(init.release()); 2423 assert(Init && "missing initializer"); 2424 2425 // Get the decls type and save a reference for later, since 2426 // CheckInitializerTypes may change it. 2427 QualType DclT = VDecl->getType(), SavT = DclT; 2428 if (VDecl->isBlockVarDecl()) { 2429 if (VDecl->hasExternalStorage()) { // C99 6.7.8p5 2430 Diag(VDecl->getLocation(), diag::err_block_extern_cant_init); 2431 VDecl->setInvalidDecl(); 2432 } else if (!VDecl->isInvalidDecl()) { 2433 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2434 VDecl->getDeclName(), DirectInit)) 2435 VDecl->setInvalidDecl(); 2436 2437 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2438 // Don't check invalid declarations to avoid emitting useless diagnostics. 2439 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2440 if (VDecl->getStorageClass() == VarDecl::Static) // C99 6.7.8p4. 2441 CheckForConstantInitializer(Init, DclT); 2442 } 2443 } 2444 } else if (VDecl->isStaticDataMember() && 2445 VDecl->getLexicalDeclContext()->isRecord()) { 2446 // This is an in-class initialization for a static data member, e.g., 2447 // 2448 // struct S { 2449 // static const int value = 17; 2450 // }; 2451 2452 // Attach the initializer 2453 VDecl->setInit(Init); 2454 2455 // C++ [class.mem]p4: 2456 // A member-declarator can contain a constant-initializer only 2457 // if it declares a static member (9.4) of const integral or 2458 // const enumeration type, see 9.4.2. 2459 QualType T = VDecl->getType(); 2460 if (!T->isDependentType() && 2461 (!Context.getCanonicalType(T).isConstQualified() || 2462 !T->isIntegralType())) { 2463 Diag(VDecl->getLocation(), diag::err_member_initialization) 2464 << VDecl->getDeclName() << Init->getSourceRange(); 2465 VDecl->setInvalidDecl(); 2466 } else { 2467 // C++ [class.static.data]p4: 2468 // If a static data member is of const integral or const 2469 // enumeration type, its declaration in the class definition 2470 // can specify a constant-initializer which shall be an 2471 // integral constant expression (5.19). 2472 if (!Init->isTypeDependent() && 2473 !Init->getType()->isIntegralType()) { 2474 // We have a non-dependent, non-integral or enumeration type. 2475 Diag(Init->getSourceRange().getBegin(), 2476 diag::err_in_class_initializer_non_integral_type) 2477 << Init->getType() << Init->getSourceRange(); 2478 VDecl->setInvalidDecl(); 2479 } else if (!Init->isTypeDependent() && !Init->isValueDependent()) { 2480 // Check whether the expression is a constant expression. 2481 llvm::APSInt Value; 2482 SourceLocation Loc; 2483 if (!Init->isIntegerConstantExpr(Value, Context, &Loc)) { 2484 Diag(Loc, diag::err_in_class_initializer_non_constant) 2485 << Init->getSourceRange(); 2486 VDecl->setInvalidDecl(); 2487 } else if (!VDecl->getType()->isDependentType()) 2488 ImpCastExprToType(Init, VDecl->getType()); 2489 } 2490 } 2491 } else if (VDecl->isFileVarDecl()) { 2492 if (VDecl->getStorageClass() == VarDecl::Extern) 2493 Diag(VDecl->getLocation(), diag::warn_extern_init); 2494 if (!VDecl->isInvalidDecl()) 2495 if (CheckInitializerTypes(Init, DclT, VDecl->getLocation(), 2496 VDecl->getDeclName(), DirectInit)) 2497 VDecl->setInvalidDecl(); 2498 2499 // C++ 3.6.2p2, allow dynamic initialization of static initializers. 2500 // Don't check invalid declarations to avoid emitting useless diagnostics. 2501 if (!getLangOptions().CPlusPlus && !VDecl->isInvalidDecl()) { 2502 // C99 6.7.8p4. All file scoped initializers need to be constant. 2503 CheckForConstantInitializer(Init, DclT); 2504 } 2505 } 2506 // If the type changed, it means we had an incomplete type that was 2507 // completed by the initializer. For example: 2508 // int ary[] = { 1, 3, 5 }; 2509 // "ary" transitions from a VariableArrayType to a ConstantArrayType. 2510 if (!VDecl->isInvalidDecl() && (DclT != SavT)) { 2511 VDecl->setType(DclT); 2512 Init->setType(DclT); 2513 } 2514 2515 // Attach the initializer to the decl. 2516 VDecl->setInit(Init); 2517 return; 2518} 2519 2520void Sema::ActOnUninitializedDecl(DeclPtrTy dcl) { 2521 Decl *RealDecl = dcl.getAs<Decl>(); 2522 2523 // If there is no declaration, there was an error parsing it. Just ignore it. 2524 if (RealDecl == 0) 2525 return; 2526 2527 if (VarDecl *Var = dyn_cast<VarDecl>(RealDecl)) { 2528 QualType Type = Var->getType(); 2529 // C++ [dcl.init.ref]p3: 2530 // The initializer can be omitted for a reference only in a 2531 // parameter declaration (8.3.5), in the declaration of a 2532 // function return type, in the declaration of a class member 2533 // within its class declaration (9.2), and where the extern 2534 // specifier is explicitly used. 2535 if (Type->isReferenceType() && !Var->hasExternalStorage()) { 2536 Diag(Var->getLocation(), diag::err_reference_var_requires_init) 2537 << Var->getDeclName() 2538 << SourceRange(Var->getLocation(), Var->getLocation()); 2539 Var->setInvalidDecl(); 2540 return; 2541 } 2542 2543 // C++ [dcl.init]p9: 2544 // 2545 // If no initializer is specified for an object, and the object 2546 // is of (possibly cv-qualified) non-POD class type (or array 2547 // thereof), the object shall be default-initialized; if the 2548 // object is of const-qualified type, the underlying class type 2549 // shall have a user-declared default constructor. 2550 if (getLangOptions().CPlusPlus) { 2551 QualType InitType = Type; 2552 if (const ArrayType *Array = Context.getAsArrayType(Type)) 2553 InitType = Array->getElementType(); 2554 if (!Var->hasExternalStorage() && InitType->isRecordType()) { 2555 const CXXConstructorDecl *Constructor = 0; 2556 if (!RequireCompleteType(Var->getLocation(), InitType, 2557 diag::err_invalid_incomplete_type_use)) 2558 Constructor 2559 = PerformInitializationByConstructor(InitType, 0, 0, 2560 Var->getLocation(), 2561 SourceRange(Var->getLocation(), 2562 Var->getLocation()), 2563 Var->getDeclName(), 2564 IK_Default); 2565 if (!Constructor) 2566 Var->setInvalidDecl(); 2567 } 2568 } 2569 2570#if 0 2571 // FIXME: Temporarily disabled because we are not properly parsing 2572 // linkage specifications on declarations, e.g., 2573 // 2574 // extern "C" const CGPoint CGPointerZero; 2575 // 2576 // C++ [dcl.init]p9: 2577 // 2578 // If no initializer is specified for an object, and the 2579 // object is of (possibly cv-qualified) non-POD class type (or 2580 // array thereof), the object shall be default-initialized; if 2581 // the object is of const-qualified type, the underlying class 2582 // type shall have a user-declared default 2583 // constructor. Otherwise, if no initializer is specified for 2584 // an object, the object and its subobjects, if any, have an 2585 // indeterminate initial value; if the object or any of its 2586 // subobjects are of const-qualified type, the program is 2587 // ill-formed. 2588 // 2589 // This isn't technically an error in C, so we don't diagnose it. 2590 // 2591 // FIXME: Actually perform the POD/user-defined default 2592 // constructor check. 2593 if (getLangOptions().CPlusPlus && 2594 Context.getCanonicalType(Type).isConstQualified() && 2595 !Var->hasExternalStorage()) 2596 Diag(Var->getLocation(), diag::err_const_var_requires_init) 2597 << Var->getName() 2598 << SourceRange(Var->getLocation(), Var->getLocation()); 2599#endif 2600 } 2601} 2602 2603Sema::DeclGroupPtrTy Sema::FinalizeDeclaratorGroup(Scope *S, DeclPtrTy *Group, 2604 unsigned NumDecls) { 2605 llvm::SmallVector<Decl*, 8> Decls; 2606 2607 for (unsigned i = 0; i != NumDecls; ++i) 2608 if (Decl *D = Group[i].getAs<Decl>()) 2609 Decls.push_back(D); 2610 2611 // Perform semantic analysis that depends on having fully processed both 2612 // the declarator and initializer. 2613 for (unsigned i = 0, e = Decls.size(); i != e; ++i) { 2614 VarDecl *IDecl = dyn_cast<VarDecl>(Decls[i]); 2615 if (!IDecl) 2616 continue; 2617 QualType T = IDecl->getType(); 2618 2619 // Block scope. C99 6.7p7: If an identifier for an object is declared with 2620 // no linkage (C99 6.2.2p6), the type for the object shall be complete... 2621 if (IDecl->isBlockVarDecl() && !IDecl->hasExternalStorage()) { 2622 if (!IDecl->isInvalidDecl() && 2623 RequireCompleteType(IDecl->getLocation(), T, 2624 diag::err_typecheck_decl_incomplete_type)) 2625 IDecl->setInvalidDecl(); 2626 } 2627 // File scope. C99 6.9.2p2: A declaration of an identifier for and 2628 // object that has file scope without an initializer, and without a 2629 // storage-class specifier or with the storage-class specifier "static", 2630 // constitutes a tentative definition. Note: A tentative definition with 2631 // external linkage is valid (C99 6.2.2p5). 2632 if (IDecl->isTentativeDefinition(Context)) { 2633 QualType CheckType = T; 2634 unsigned DiagID = diag::err_typecheck_decl_incomplete_type; 2635 2636 const IncompleteArrayType *ArrayT = Context.getAsIncompleteArrayType(T); 2637 if (ArrayT) { 2638 CheckType = ArrayT->getElementType(); 2639 DiagID = diag::err_illegal_decl_array_incomplete_type; 2640 } 2641 2642 if (IDecl->isInvalidDecl()) { 2643 // Do nothing with invalid declarations 2644 } else if ((ArrayT || IDecl->getStorageClass() == VarDecl::Static) && 2645 RequireCompleteType(IDecl->getLocation(), CheckType, DiagID)) { 2646 // C99 6.9.2p3: If the declaration of an identifier for an object is 2647 // a tentative definition and has internal linkage (C99 6.2.2p3), the 2648 // declared type shall not be an incomplete type. 2649 IDecl->setInvalidDecl(); 2650 } 2651 } 2652 } 2653 return DeclGroupPtrTy::make(DeclGroupRef::Create(Context, 2654 &Decls[0], Decls.size())); 2655} 2656 2657 2658/// ActOnParamDeclarator - Called from Parser::ParseFunctionDeclarator() 2659/// to introduce parameters into function prototype scope. 2660Sema::DeclPtrTy 2661Sema::ActOnParamDeclarator(Scope *S, Declarator &D) { 2662 const DeclSpec &DS = D.getDeclSpec(); 2663 2664 // Verify C99 6.7.5.3p2: The only SCS allowed is 'register'. 2665 VarDecl::StorageClass StorageClass = VarDecl::None; 2666 if (DS.getStorageClassSpec() == DeclSpec::SCS_register) { 2667 StorageClass = VarDecl::Register; 2668 } else if (DS.getStorageClassSpec() != DeclSpec::SCS_unspecified) { 2669 Diag(DS.getStorageClassSpecLoc(), 2670 diag::err_invalid_storage_class_in_func_decl); 2671 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2672 } 2673 if (DS.isThreadSpecified()) { 2674 Diag(DS.getThreadSpecLoc(), 2675 diag::err_invalid_storage_class_in_func_decl); 2676 D.getMutableDeclSpec().ClearStorageClassSpecs(); 2677 } 2678 DiagnoseFunctionSpecifiers(D); 2679 2680 // Check that there are no default arguments inside the type of this 2681 // parameter (C++ only). 2682 if (getLangOptions().CPlusPlus) 2683 CheckExtraCXXDefaultArguments(D); 2684 2685 // In this context, we *do not* check D.getInvalidType(). If the declarator 2686 // type was invalid, GetTypeForDeclarator() still returns a "valid" type, 2687 // though it will not reflect the user specified type. 2688 QualType parmDeclType = GetTypeForDeclarator(D, S); 2689 if (parmDeclType.isNull()) { 2690 D.setInvalidType(true); 2691 parmDeclType = Context.IntTy; 2692 } 2693 2694 // TODO: CHECK FOR CONFLICTS, multiple decls with same name in one scope. 2695 // Can this happen for params? We already checked that they don't conflict 2696 // among each other. Here they can only shadow globals, which is ok. 2697 IdentifierInfo *II = D.getIdentifier(); 2698 if (II) { 2699 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2700 if (PrevDecl->isTemplateParameter()) { 2701 // Maybe we will complain about the shadowed template parameter. 2702 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2703 // Just pretend that we didn't see the previous declaration. 2704 PrevDecl = 0; 2705 } else if (S->isDeclScope(DeclPtrTy::make(PrevDecl))) { 2706 Diag(D.getIdentifierLoc(), diag::err_param_redefinition) << II; 2707 2708 // Recover by removing the name 2709 II = 0; 2710 D.SetIdentifier(0, D.getIdentifierLoc()); 2711 } 2712 } 2713 } 2714 2715 // Parameters can not be abstract class types. 2716 // For record types, this is done by the AbstractClassUsageDiagnoser once 2717 // the class has been completely parsed. 2718 if (!CurContext->isRecord() && 2719 RequireNonAbstractType(D.getIdentifierLoc(), parmDeclType, 2720 diag::err_abstract_type_in_decl, 2721 AbstractParamType)) 2722 D.setInvalidType(true); 2723 2724 QualType T = adjustParameterType(parmDeclType); 2725 2726 ParmVarDecl *New; 2727 if (T == parmDeclType) // parameter type did not need adjustment 2728 New = ParmVarDecl::Create(Context, CurContext, 2729 D.getIdentifierLoc(), II, 2730 parmDeclType, StorageClass, 2731 0); 2732 else // keep track of both the adjusted and unadjusted types 2733 New = OriginalParmVarDecl::Create(Context, CurContext, 2734 D.getIdentifierLoc(), II, T, 2735 parmDeclType, StorageClass, 0); 2736 2737 if (D.getInvalidType()) 2738 New->setInvalidDecl(); 2739 2740 // Parameter declarators cannot be interface types. All ObjC objects are 2741 // passed by reference. 2742 if (T->isObjCInterfaceType()) { 2743 Diag(D.getIdentifierLoc(), 2744 diag::err_object_cannot_be_passed_returned_by_value) << 1 << T; 2745 New->setInvalidDecl(); 2746 } 2747 2748 // Parameter declarators cannot be qualified (C++ [dcl.meaning]p1). 2749 if (D.getCXXScopeSpec().isSet()) { 2750 Diag(D.getIdentifierLoc(), diag::err_qualified_param_declarator) 2751 << D.getCXXScopeSpec().getRange(); 2752 New->setInvalidDecl(); 2753 } 2754 2755 // Add the parameter declaration into this scope. 2756 S->AddDecl(DeclPtrTy::make(New)); 2757 if (II) 2758 IdResolver.AddDecl(New); 2759 2760 ProcessDeclAttributes(New, D); 2761 return DeclPtrTy::make(New); 2762} 2763 2764void Sema::ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D, 2765 SourceLocation LocAfterDecls) { 2766 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2767 "Not a function declarator!"); 2768 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2769 2770 // Verify 6.9.1p6: 'every identifier in the identifier list shall be declared' 2771 // for a K&R function. 2772 if (!FTI.hasPrototype) { 2773 for (int i = FTI.NumArgs; i != 0; /* decrement in loop */) { 2774 --i; 2775 if (FTI.ArgInfo[i].Param == 0) { 2776 std::string Code = " int "; 2777 Code += FTI.ArgInfo[i].Ident->getName(); 2778 Code += ";\n"; 2779 Diag(FTI.ArgInfo[i].IdentLoc, diag::ext_param_not_declared) 2780 << FTI.ArgInfo[i].Ident 2781 << CodeModificationHint::CreateInsertion(LocAfterDecls, Code); 2782 2783 // Implicitly declare the argument as type 'int' for lack of a better 2784 // type. 2785 DeclSpec DS; 2786 const char* PrevSpec; // unused 2787 DS.SetTypeSpecType(DeclSpec::TST_int, FTI.ArgInfo[i].IdentLoc, 2788 PrevSpec); 2789 Declarator ParamD(DS, Declarator::KNRTypeListContext); 2790 ParamD.SetIdentifier(FTI.ArgInfo[i].Ident, FTI.ArgInfo[i].IdentLoc); 2791 FTI.ArgInfo[i].Param = ActOnParamDeclarator(S, ParamD); 2792 } 2793 } 2794 } 2795} 2796 2797Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, 2798 Declarator &D) { 2799 assert(getCurFunctionDecl() == 0 && "Function parsing confused"); 2800 assert(D.getTypeObject(0).Kind == DeclaratorChunk::Function && 2801 "Not a function declarator!"); 2802 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 2803 2804 if (FTI.hasPrototype) { 2805 // FIXME: Diagnose arguments without names in C. 2806 } 2807 2808 Scope *ParentScope = FnBodyScope->getParent(); 2809 2810 DeclPtrTy DP = ActOnDeclarator(ParentScope, D, /*IsFunctionDefinition=*/true); 2811 return ActOnStartOfFunctionDef(FnBodyScope, DP); 2812} 2813 2814Sema::DeclPtrTy Sema::ActOnStartOfFunctionDef(Scope *FnBodyScope, DeclPtrTy D) { 2815 FunctionDecl *FD = cast<FunctionDecl>(D.getAs<Decl>()); 2816 2817 // See if this is a redefinition. 2818 const FunctionDecl *Definition; 2819 if (FD->getBody(Definition)) { 2820 Diag(FD->getLocation(), diag::err_redefinition) << FD->getDeclName(); 2821 Diag(Definition->getLocation(), diag::note_previous_definition); 2822 } 2823 2824 // Builtin functions cannot be defined. 2825 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 2826 if (!Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID)) { 2827 Diag(FD->getLocation(), diag::err_builtin_definition) << FD; 2828 FD->setInvalidDecl(); 2829 } 2830 } 2831 2832 // The return type of a function definition must be complete 2833 // (C99 6.9.1p3, C++ [dcl.fct]p6). 2834 QualType ResultType = FD->getResultType(); 2835 if (!ResultType->isDependentType() && !ResultType->isVoidType() && 2836 RequireCompleteType(FD->getLocation(), ResultType, 2837 diag::err_func_def_incomplete_result)) 2838 FD->setInvalidDecl(); 2839 2840 // GNU warning -Wmissing-prototypes: 2841 // Warn if a global function is defined without a previous 2842 // prototype declaration. This warning is issued even if the 2843 // definition itself provides a prototype. The aim is to detect 2844 // global functions that fail to be declared in header files. 2845 if (!FD->isInvalidDecl() && FD->isGlobal() && !isa<CXXMethodDecl>(FD) && 2846 !FD->isMain()) { 2847 bool MissingPrototype = true; 2848 for (const FunctionDecl *Prev = FD->getPreviousDeclaration(); 2849 Prev; Prev = Prev->getPreviousDeclaration()) { 2850 // Ignore any declarations that occur in function or method 2851 // scope, because they aren't visible from the header. 2852 if (Prev->getDeclContext()->isFunctionOrMethod()) 2853 continue; 2854 2855 MissingPrototype = !Prev->getType()->isFunctionProtoType(); 2856 break; 2857 } 2858 2859 if (MissingPrototype) 2860 Diag(FD->getLocation(), diag::warn_missing_prototype) << FD; 2861 } 2862 2863 PushDeclContext(FnBodyScope, FD); 2864 2865 // Check the validity of our function parameters 2866 CheckParmsForFunctionDef(FD); 2867 2868 // Introduce our parameters into the function scope 2869 for (unsigned p = 0, NumParams = FD->getNumParams(); p < NumParams; ++p) { 2870 ParmVarDecl *Param = FD->getParamDecl(p); 2871 Param->setOwningFunction(FD); 2872 2873 // If this has an identifier, add it to the scope stack. 2874 if (Param->getIdentifier()) 2875 PushOnScopeChains(Param, FnBodyScope); 2876 } 2877 2878 // Checking attributes of current function definition 2879 // dllimport attribute. 2880 if (FD->getAttr<DLLImportAttr>() && (!FD->getAttr<DLLExportAttr>())) { 2881 // dllimport attribute cannot be applied to definition. 2882 if (!(FD->getAttr<DLLImportAttr>())->isInherited()) { 2883 Diag(FD->getLocation(), 2884 diag::err_attribute_can_be_applied_only_to_symbol_declaration) 2885 << "dllimport"; 2886 FD->setInvalidDecl(); 2887 return DeclPtrTy::make(FD); 2888 } else { 2889 // If a symbol previously declared dllimport is later defined, the 2890 // attribute is ignored in subsequent references, and a warning is 2891 // emitted. 2892 Diag(FD->getLocation(), 2893 diag::warn_redeclaration_without_attribute_prev_attribute_ignored) 2894 << FD->getNameAsCString() << "dllimport"; 2895 } 2896 } 2897 return DeclPtrTy::make(FD); 2898} 2899 2900static bool StatementCreatesScope(Stmt* S) { 2901 2902 if (DeclStmt *DS = dyn_cast<DeclStmt>(S)) { 2903 for (DeclStmt::decl_iterator I = DS->decl_begin(), E = DS->decl_end(); 2904 I != E; ++I) { 2905 if (VarDecl *D = dyn_cast<VarDecl>(*I)) { 2906 if (D->getType()->isVariablyModifiedType() || 2907 D->hasAttr<CleanupAttr>()) 2908 return true; 2909 } else if (TypedefDecl *D = dyn_cast<TypedefDecl>(*I)) { 2910 if (D->getUnderlyingType()->isVariablyModifiedType()) 2911 return true; 2912 } 2913 } 2914 } 2915 return false; 2916} 2917 2918 2919void Sema::RecursiveCalcLabelScopes(llvm::DenseMap<Stmt*, void*>& LabelScopeMap, 2920 llvm::DenseMap<void*, Stmt*>& PopScopeMap, 2921 std::vector<void*>& ScopeStack, 2922 Stmt* CurStmt, 2923 Stmt* ParentCompoundStmt) { 2924 for (Stmt::child_iterator i = CurStmt->child_begin(); 2925 i != CurStmt->child_end(); ++i) { 2926 if (!*i) continue; 2927 if (StatementCreatesScope(*i)) { 2928 ScopeStack.push_back(*i); 2929 PopScopeMap[*i] = ParentCompoundStmt; 2930 } else if (ObjCAtTryStmt *AT = dyn_cast<ObjCAtTryStmt>(*i)) { 2931 ScopeStack.push_back(*i); 2932 PopScopeMap[*i] = AT->getTryBody(); 2933 } else if (ObjCAtCatchStmt *AC = dyn_cast<ObjCAtCatchStmt>(*i)) { 2934 ScopeStack.push_back(*i); 2935 PopScopeMap[*i] = AC->getCatchBody(); 2936 } else if (ObjCAtFinallyStmt *AF = dyn_cast<ObjCAtFinallyStmt>(*i)) { 2937 ScopeStack.push_back(*i); 2938 PopScopeMap[*i] = AF->getFinallyBody(); 2939 } else if (isa<LabelStmt>(CurStmt)) { 2940 LabelScopeMap[CurStmt] = ScopeStack.size() ? ScopeStack.back() : 0; 2941 } 2942 if (isa<DeclStmt>(*i)) continue; 2943 Stmt* CurCompound = isa<CompoundStmt>(*i) ? *i : ParentCompoundStmt; 2944 RecursiveCalcLabelScopes(LabelScopeMap, PopScopeMap, ScopeStack, 2945 *i, CurCompound); 2946 } 2947 while (ScopeStack.size() && PopScopeMap[ScopeStack.back()] == CurStmt) { 2948 ScopeStack.pop_back(); 2949 } 2950} 2951 2952void Sema::RecursiveCalcJumpScopes(llvm::DenseMap<Stmt*, void*>& LabelScopeMap, 2953 llvm::DenseMap<void*, Stmt*>& PopScopeMap, 2954 llvm::DenseMap<Stmt*, void*>& GotoScopeMap, 2955 std::vector<void*>& ScopeStack, 2956 Stmt* CurStmt) { 2957 for (Stmt::child_iterator i = CurStmt->child_begin(); 2958 i != CurStmt->child_end(); ++i) { 2959 if (!*i) continue; 2960 if (StatementCreatesScope(*i)) { 2961 ScopeStack.push_back(*i); 2962 } else if (GotoStmt* GS = dyn_cast<GotoStmt>(*i)) { 2963 void* LScope = LabelScopeMap[GS->getLabel()]; 2964 if (LScope) { 2965 bool foundScopeInStack = false; 2966 for (unsigned i = ScopeStack.size(); i > 0; --i) { 2967 if (LScope == ScopeStack[i-1]) { 2968 foundScopeInStack = true; 2969 break; 2970 } 2971 } 2972 if (!foundScopeInStack) { 2973 Diag(GS->getSourceRange().getBegin(), diag::err_goto_into_scope); 2974 } 2975 } 2976 } 2977 if (isa<DeclStmt>(*i)) continue; 2978 RecursiveCalcJumpScopes(LabelScopeMap, PopScopeMap, GotoScopeMap, 2979 ScopeStack, *i); 2980 } 2981 while (ScopeStack.size() && PopScopeMap[ScopeStack.back()] == CurStmt) { 2982 ScopeStack.pop_back(); 2983 } 2984} 2985 2986Sema::DeclPtrTy Sema::ActOnFinishFunctionBody(DeclPtrTy D, StmtArg BodyArg) { 2987 Decl *dcl = D.getAs<Decl>(); 2988 Stmt *Body = static_cast<Stmt*>(BodyArg.release()); 2989 if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(dcl)) { 2990 FD->setBody(cast<CompoundStmt>(Body)); 2991 assert(FD == getCurFunctionDecl() && "Function parsing confused"); 2992 } else if (ObjCMethodDecl *MD = dyn_cast_or_null<ObjCMethodDecl>(dcl)) { 2993 assert(MD == getCurMethodDecl() && "Method parsing confused"); 2994 MD->setBody(cast<CompoundStmt>(Body)); 2995 } else { 2996 Body->Destroy(Context); 2997 return DeclPtrTy(); 2998 } 2999 PopDeclContext(); 3000 // Verify and clean out per-function state. 3001 3002 bool HaveLabels = !LabelMap.empty(); 3003 // Check goto/label use. 3004 for (llvm::DenseMap<IdentifierInfo*, LabelStmt*>::iterator 3005 I = LabelMap.begin(), E = LabelMap.end(); I != E; ++I) { 3006 // Verify that we have no forward references left. If so, there was a goto 3007 // or address of a label taken, but no definition of it. Label fwd 3008 // definitions are indicated with a null substmt. 3009 if (I->second->getSubStmt() == 0) { 3010 LabelStmt *L = I->second; 3011 // Emit error. 3012 Diag(L->getIdentLoc(), diag::err_undeclared_label_use) << L->getName(); 3013 3014 // At this point, we have gotos that use the bogus label. Stitch it into 3015 // the function body so that they aren't leaked and that the AST is well 3016 // formed. 3017 if (Body) { 3018#if 0 3019 // FIXME: Why do this? Having a 'push_back' in CompoundStmt is ugly, 3020 // and the AST is malformed anyway. We should just blow away 'L'. 3021 L->setSubStmt(new (Context) NullStmt(L->getIdentLoc())); 3022 cast<CompoundStmt>(Body)->push_back(L); 3023#else 3024 L->Destroy(Context); 3025#endif 3026 } else { 3027 // The whole function wasn't parsed correctly, just delete this. 3028 L->Destroy(Context); 3029 } 3030 } 3031 } 3032 LabelMap.clear(); 3033 3034 if (!Body) return D; 3035 3036 if (HaveLabels) { 3037 llvm::DenseMap<Stmt*, void*> LabelScopeMap; 3038 llvm::DenseMap<void*, Stmt*> PopScopeMap; 3039 llvm::DenseMap<Stmt*, void*> GotoScopeMap; 3040 std::vector<void*> ScopeStack; 3041 RecursiveCalcLabelScopes(LabelScopeMap, PopScopeMap, ScopeStack, Body, Body); 3042 RecursiveCalcJumpScopes(LabelScopeMap, PopScopeMap, GotoScopeMap, ScopeStack, Body); 3043 } 3044 3045 return D; 3046} 3047 3048/// ImplicitlyDefineFunction - An undeclared identifier was used in a function 3049/// call, forming a call to an implicitly defined function (per C99 6.5.1p2). 3050NamedDecl *Sema::ImplicitlyDefineFunction(SourceLocation Loc, 3051 IdentifierInfo &II, Scope *S) { 3052 // Before we produce a declaration for an implicitly defined 3053 // function, see whether there was a locally-scoped declaration of 3054 // this name as a function or variable. If so, use that 3055 // (non-visible) declaration, and complain about it. 3056 llvm::DenseMap<DeclarationName, NamedDecl *>::iterator Pos 3057 = LocallyScopedExternalDecls.find(&II); 3058 if (Pos != LocallyScopedExternalDecls.end()) { 3059 Diag(Loc, diag::warn_use_out_of_scope_declaration) << Pos->second; 3060 Diag(Pos->second->getLocation(), diag::note_previous_declaration); 3061 return Pos->second; 3062 } 3063 3064 // Extension in C99. Legal in C90, but warn about it. 3065 if (getLangOptions().C99) 3066 Diag(Loc, diag::ext_implicit_function_decl) << &II; 3067 else 3068 Diag(Loc, diag::warn_implicit_function_decl) << &II; 3069 3070 // FIXME: handle stuff like: 3071 // void foo() { extern float X(); } 3072 // void bar() { X(); } <-- implicit decl for X in another scope. 3073 3074 // Set a Declarator for the implicit definition: int foo(); 3075 const char *Dummy; 3076 DeclSpec DS; 3077 bool Error = DS.SetTypeSpecType(DeclSpec::TST_int, Loc, Dummy); 3078 Error = Error; // Silence warning. 3079 assert(!Error && "Error setting up implicit decl!"); 3080 Declarator D(DS, Declarator::BlockContext); 3081 D.AddTypeInfo(DeclaratorChunk::getFunction(false, false, SourceLocation(), 3082 0, 0, 0, Loc, D), 3083 SourceLocation()); 3084 D.SetIdentifier(&II, Loc); 3085 3086 // Insert this function into translation-unit scope. 3087 3088 DeclContext *PrevDC = CurContext; 3089 CurContext = Context.getTranslationUnitDecl(); 3090 3091 FunctionDecl *FD = 3092 dyn_cast<FunctionDecl>(ActOnDeclarator(TUScope, D, DeclPtrTy()).getAs<Decl>()); 3093 FD->setImplicit(); 3094 3095 CurContext = PrevDC; 3096 3097 AddKnownFunctionAttributes(FD); 3098 3099 return FD; 3100} 3101 3102/// \brief Adds any function attributes that we know a priori based on 3103/// the declaration of this function. 3104/// 3105/// These attributes can apply both to implicitly-declared builtins 3106/// (like __builtin___printf_chk) or to library-declared functions 3107/// like NSLog or printf. 3108void Sema::AddKnownFunctionAttributes(FunctionDecl *FD) { 3109 if (FD->isInvalidDecl()) 3110 return; 3111 3112 // If this is a built-in function, map its builtin attributes to 3113 // actual attributes. 3114 if (unsigned BuiltinID = FD->getBuiltinID(Context)) { 3115 // Handle printf-formatting attributes. 3116 unsigned FormatIdx; 3117 bool HasVAListArg; 3118 if (Context.BuiltinInfo.isPrintfLike(BuiltinID, FormatIdx, HasVAListArg)) { 3119 if (!FD->getAttr<FormatAttr>()) 3120 FD->addAttr(::new (Context) FormatAttr("printf", FormatIdx + 1, 3121 FormatIdx + 2)); 3122 } 3123 3124 // Mark const if we don't care about errno and that is the only 3125 // thing preventing the function from being const. This allows 3126 // IRgen to use LLVM intrinsics for such functions. 3127 if (!getLangOptions().MathErrno && 3128 Context.BuiltinInfo.isConstWithoutErrno(BuiltinID)) { 3129 if (!FD->getAttr<ConstAttr>()) 3130 FD->addAttr(::new (Context) ConstAttr()); 3131 } 3132 } 3133 3134 IdentifierInfo *Name = FD->getIdentifier(); 3135 if (!Name) 3136 return; 3137 if ((!getLangOptions().CPlusPlus && 3138 FD->getDeclContext()->isTranslationUnit()) || 3139 (isa<LinkageSpecDecl>(FD->getDeclContext()) && 3140 cast<LinkageSpecDecl>(FD->getDeclContext())->getLanguage() == 3141 LinkageSpecDecl::lang_c)) { 3142 // Okay: this could be a libc/libm/Objective-C function we know 3143 // about. 3144 } else 3145 return; 3146 3147 unsigned KnownID; 3148 for (KnownID = 0; KnownID != id_num_known_functions; ++KnownID) 3149 if (KnownFunctionIDs[KnownID] == Name) 3150 break; 3151 3152 switch (KnownID) { 3153 case id_NSLog: 3154 case id_NSLogv: 3155 if (const FormatAttr *Format = FD->getAttr<FormatAttr>()) { 3156 // FIXME: We known better than our headers. 3157 const_cast<FormatAttr *>(Format)->setType("printf"); 3158 } else 3159 FD->addAttr(::new (Context) FormatAttr("printf", 1, 2)); 3160 break; 3161 3162 case id_asprintf: 3163 case id_vasprintf: 3164 if (!FD->getAttr<FormatAttr>()) 3165 FD->addAttr(::new (Context) FormatAttr("printf", 2, 3)); 3166 break; 3167 3168 default: 3169 // Unknown function or known function without any attributes to 3170 // add. Do nothing. 3171 break; 3172 } 3173} 3174 3175TypedefDecl *Sema::ParseTypedefDecl(Scope *S, Declarator &D, QualType T) { 3176 assert(D.getIdentifier() && "Wrong callback for declspec without declarator"); 3177 assert(!T.isNull() && "GetTypeForDeclarator() returned null type"); 3178 3179 // Scope manipulation handled by caller. 3180 TypedefDecl *NewTD = TypedefDecl::Create(Context, CurContext, 3181 D.getIdentifierLoc(), 3182 D.getIdentifier(), 3183 T); 3184 3185 if (TagType *TT = dyn_cast<TagType>(T)) { 3186 TagDecl *TD = TT->getDecl(); 3187 3188 // If the TagDecl that the TypedefDecl points to is an anonymous decl 3189 // keep track of the TypedefDecl. 3190 if (!TD->getIdentifier() && !TD->getTypedefForAnonDecl()) 3191 TD->setTypedefForAnonDecl(NewTD); 3192 } 3193 3194 if (D.getInvalidType()) 3195 NewTD->setInvalidDecl(); 3196 return NewTD; 3197} 3198 3199/// ActOnTag - This is invoked when we see 'struct foo' or 'struct {'. In the 3200/// former case, Name will be non-null. In the later case, Name will be null. 3201/// TagSpec indicates what kind of tag this is. TK indicates whether this is a 3202/// reference/declaration/definition of a tag. 3203Sema::DeclPtrTy Sema::ActOnTag(Scope *S, unsigned TagSpec, TagKind TK, 3204 SourceLocation KWLoc, const CXXScopeSpec &SS, 3205 IdentifierInfo *Name, SourceLocation NameLoc, 3206 AttributeList *Attr, AccessSpecifier AS) { 3207 // If this is not a definition, it must have a name. 3208 assert((Name != 0 || TK == TK_Definition) && 3209 "Nameless record must be a definition!"); 3210 3211 TagDecl::TagKind Kind; 3212 switch (TagSpec) { 3213 default: assert(0 && "Unknown tag type!"); 3214 case DeclSpec::TST_struct: Kind = TagDecl::TK_struct; break; 3215 case DeclSpec::TST_union: Kind = TagDecl::TK_union; break; 3216 case DeclSpec::TST_class: Kind = TagDecl::TK_class; break; 3217 case DeclSpec::TST_enum: Kind = TagDecl::TK_enum; break; 3218 } 3219 3220 DeclContext *SearchDC = CurContext; 3221 DeclContext *DC = CurContext; 3222 NamedDecl *PrevDecl = 0; 3223 3224 bool Invalid = false; 3225 3226 if (Name && SS.isNotEmpty()) { 3227 // We have a nested-name tag ('struct foo::bar'). 3228 3229 // Check for invalid 'foo::'. 3230 if (SS.isInvalid()) { 3231 Name = 0; 3232 goto CreateNewDecl; 3233 } 3234 3235 // FIXME: RequireCompleteDeclContext(SS)? 3236 DC = computeDeclContext(SS); 3237 SearchDC = DC; 3238 // Look-up name inside 'foo::'. 3239 PrevDecl = dyn_cast_or_null<TagDecl>( 3240 LookupQualifiedName(DC, Name, LookupTagName, true).getAsDecl()); 3241 3242 // A tag 'foo::bar' must already exist. 3243 if (PrevDecl == 0) { 3244 Diag(NameLoc, diag::err_not_tag_in_scope) << Name << SS.getRange(); 3245 Name = 0; 3246 goto CreateNewDecl; 3247 } 3248 } else if (Name) { 3249 // If this is a named struct, check to see if there was a previous forward 3250 // declaration or definition. 3251 // FIXME: We're looking into outer scopes here, even when we 3252 // shouldn't be. Doing so can result in ambiguities that we 3253 // shouldn't be diagnosing. 3254 LookupResult R = LookupName(S, Name, LookupTagName, 3255 /*RedeclarationOnly=*/(TK != TK_Reference)); 3256 if (R.isAmbiguous()) { 3257 DiagnoseAmbiguousLookup(R, Name, NameLoc); 3258 // FIXME: This is not best way to recover from case like: 3259 // 3260 // struct S s; 3261 // 3262 // causes needless "incomplete type" error later. 3263 Name = 0; 3264 PrevDecl = 0; 3265 Invalid = true; 3266 } 3267 else 3268 PrevDecl = R; 3269 3270 if (!getLangOptions().CPlusPlus && TK != TK_Reference) { 3271 // FIXME: This makes sure that we ignore the contexts associated 3272 // with C structs, unions, and enums when looking for a matching 3273 // tag declaration or definition. See the similar lookup tweak 3274 // in Sema::LookupName; is there a better way to deal with this? 3275 while (isa<RecordDecl>(SearchDC) || isa<EnumDecl>(SearchDC)) 3276 SearchDC = SearchDC->getParent(); 3277 } 3278 } 3279 3280 if (PrevDecl && PrevDecl->isTemplateParameter()) { 3281 // Maybe we will complain about the shadowed template parameter. 3282 DiagnoseTemplateParameterShadow(NameLoc, PrevDecl); 3283 // Just pretend that we didn't see the previous declaration. 3284 PrevDecl = 0; 3285 } 3286 3287 if (PrevDecl) { 3288 // Check whether the previous declaration is usable. 3289 (void)DiagnoseUseOfDecl(PrevDecl, NameLoc); 3290 3291 if (TagDecl *PrevTagDecl = dyn_cast<TagDecl>(PrevDecl)) { 3292 // If this is a use of a previous tag, or if the tag is already declared 3293 // in the same scope (so that the definition/declaration completes or 3294 // rementions the tag), reuse the decl. 3295 if (TK == TK_Reference || isDeclInScope(PrevDecl, SearchDC, S)) { 3296 // Make sure that this wasn't declared as an enum and now used as a 3297 // struct or something similar. 3298 if (PrevTagDecl->getTagKind() != Kind) { 3299 bool SafeToContinue 3300 = (PrevTagDecl->getTagKind() != TagDecl::TK_enum && 3301 Kind != TagDecl::TK_enum); 3302 if (SafeToContinue) 3303 Diag(KWLoc, diag::err_use_with_wrong_tag) 3304 << Name 3305 << CodeModificationHint::CreateReplacement(SourceRange(KWLoc), 3306 PrevTagDecl->getKindName()); 3307 else 3308 Diag(KWLoc, diag::err_use_with_wrong_tag) << Name; 3309 Diag(PrevDecl->getLocation(), diag::note_previous_use); 3310 3311 if (SafeToContinue) 3312 Kind = PrevTagDecl->getTagKind(); 3313 else { 3314 // Recover by making this an anonymous redefinition. 3315 Name = 0; 3316 PrevDecl = 0; 3317 Invalid = true; 3318 } 3319 } 3320 3321 if (!Invalid) { 3322 // If this is a use, just return the declaration we found. 3323 3324 // FIXME: In the future, return a variant or some other clue 3325 // for the consumer of this Decl to know it doesn't own it. 3326 // For our current ASTs this shouldn't be a problem, but will 3327 // need to be changed with DeclGroups. 3328 if (TK == TK_Reference) 3329 return DeclPtrTy::make(PrevDecl); 3330 3331 // Diagnose attempts to redefine a tag. 3332 if (TK == TK_Definition) { 3333 if (TagDecl *Def = PrevTagDecl->getDefinition(Context)) { 3334 Diag(NameLoc, diag::err_redefinition) << Name; 3335 Diag(Def->getLocation(), diag::note_previous_definition); 3336 // If this is a redefinition, recover by making this 3337 // struct be anonymous, which will make any later 3338 // references get the previous definition. 3339 Name = 0; 3340 PrevDecl = 0; 3341 Invalid = true; 3342 } else { 3343 // If the type is currently being defined, complain 3344 // about a nested redefinition. 3345 TagType *Tag = cast<TagType>(Context.getTagDeclType(PrevTagDecl)); 3346 if (Tag->isBeingDefined()) { 3347 Diag(NameLoc, diag::err_nested_redefinition) << Name; 3348 Diag(PrevTagDecl->getLocation(), 3349 diag::note_previous_definition); 3350 Name = 0; 3351 PrevDecl = 0; 3352 Invalid = true; 3353 } 3354 } 3355 3356 // Okay, this is definition of a previously declared or referenced 3357 // tag PrevDecl. We're going to create a new Decl for it. 3358 } 3359 } 3360 // If we get here we have (another) forward declaration or we 3361 // have a definition. Just create a new decl. 3362 } else { 3363 // If we get here, this is a definition of a new tag type in a nested 3364 // scope, e.g. "struct foo; void bar() { struct foo; }", just create a 3365 // new decl/type. We set PrevDecl to NULL so that the entities 3366 // have distinct types. 3367 PrevDecl = 0; 3368 } 3369 // If we get here, we're going to create a new Decl. If PrevDecl 3370 // is non-NULL, it's a definition of the tag declared by 3371 // PrevDecl. If it's NULL, we have a new definition. 3372 } else { 3373 // PrevDecl is a namespace, template, or anything else 3374 // that lives in the IDNS_Tag identifier namespace. 3375 if (isDeclInScope(PrevDecl, SearchDC, S)) { 3376 // The tag name clashes with a namespace name, issue an error and 3377 // recover by making this tag be anonymous. 3378 Diag(NameLoc, diag::err_redefinition_different_kind) << Name; 3379 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 3380 Name = 0; 3381 PrevDecl = 0; 3382 Invalid = true; 3383 } else { 3384 // The existing declaration isn't relevant to us; we're in a 3385 // new scope, so clear out the previous declaration. 3386 PrevDecl = 0; 3387 } 3388 } 3389 } else if (TK == TK_Reference && SS.isEmpty() && Name && 3390 (Kind != TagDecl::TK_enum || !getLangOptions().CPlusPlus)) { 3391 // C.scope.pdecl]p5: 3392 // -- for an elaborated-type-specifier of the form 3393 // 3394 // class-key identifier 3395 // 3396 // if the elaborated-type-specifier is used in the 3397 // decl-specifier-seq or parameter-declaration-clause of a 3398 // function defined in namespace scope, the identifier is 3399 // declared as a class-name in the namespace that contains 3400 // the declaration; otherwise, except as a friend 3401 // declaration, the identifier is declared in the smallest 3402 // non-class, non-function-prototype scope that contains the 3403 // declaration. 3404 // 3405 // C99 6.7.2.3p8 has a similar (but not identical!) provision for 3406 // C structs and unions. 3407 // 3408 // GNU C also supports this behavior as part of its incomplete 3409 // enum types extension, while GNU C++ does not. 3410 // 3411 // Find the context where we'll be declaring the tag. 3412 // FIXME: We would like to maintain the current DeclContext as the 3413 // lexical context, 3414 while (SearchDC->isRecord()) 3415 SearchDC = SearchDC->getParent(); 3416 3417 // Find the scope where we'll be declaring the tag. 3418 while (S->isClassScope() || 3419 (getLangOptions().CPlusPlus && S->isFunctionPrototypeScope()) || 3420 ((S->getFlags() & Scope::DeclScope) == 0) || 3421 (S->getEntity() && 3422 ((DeclContext *)S->getEntity())->isTransparentContext())) 3423 S = S->getParent(); 3424 } 3425 3426CreateNewDecl: 3427 3428 // If there is an identifier, use the location of the identifier as the 3429 // location of the decl, otherwise use the location of the struct/union 3430 // keyword. 3431 SourceLocation Loc = NameLoc.isValid() ? NameLoc : KWLoc; 3432 3433 // Otherwise, create a new declaration. If there is a previous 3434 // declaration of the same entity, the two will be linked via 3435 // PrevDecl. 3436 TagDecl *New; 3437 3438 if (Kind == TagDecl::TK_enum) { 3439 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3440 // enum X { A, B, C } D; D should chain to X. 3441 New = EnumDecl::Create(Context, SearchDC, Loc, Name, 3442 cast_or_null<EnumDecl>(PrevDecl)); 3443 // If this is an undefined enum, warn. 3444 if (TK != TK_Definition && !Invalid) { 3445 unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum 3446 : diag::ext_forward_ref_enum; 3447 Diag(Loc, DK); 3448 } 3449 } else { 3450 // struct/union/class 3451 3452 // FIXME: Tag decls should be chained to any simultaneous vardecls, e.g.: 3453 // struct X { int A; } D; D should chain to X. 3454 if (getLangOptions().CPlusPlus) 3455 // FIXME: Look for a way to use RecordDecl for simple structs. 3456 New = CXXRecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3457 cast_or_null<CXXRecordDecl>(PrevDecl)); 3458 else 3459 New = RecordDecl::Create(Context, Kind, SearchDC, Loc, Name, 3460 cast_or_null<RecordDecl>(PrevDecl)); 3461 } 3462 3463 if (Kind != TagDecl::TK_enum) { 3464 // Handle #pragma pack: if the #pragma pack stack has non-default 3465 // alignment, make up a packed attribute for this decl. These 3466 // attributes are checked when the ASTContext lays out the 3467 // structure. 3468 // 3469 // It is important for implementing the correct semantics that this 3470 // happen here (in act on tag decl). The #pragma pack stack is 3471 // maintained as a result of parser callbacks which can occur at 3472 // many points during the parsing of a struct declaration (because 3473 // the #pragma tokens are effectively skipped over during the 3474 // parsing of the struct). 3475 if (unsigned Alignment = getPragmaPackAlignment()) 3476 New->addAttr(::new (Context) PackedAttr(Alignment * 8)); 3477 } 3478 3479 if (getLangOptions().CPlusPlus && SS.isEmpty() && Name && !Invalid) { 3480 // C++ [dcl.typedef]p3: 3481 // [...] Similarly, in a given scope, a class or enumeration 3482 // shall not be declared with the same name as a typedef-name 3483 // that is declared in that scope and refers to a type other 3484 // than the class or enumeration itself. 3485 LookupResult Lookup = LookupName(S, Name, LookupOrdinaryName, true); 3486 TypedefDecl *PrevTypedef = 0; 3487 if (Lookup.getKind() == LookupResult::Found) 3488 PrevTypedef = dyn_cast<TypedefDecl>(Lookup.getAsDecl()); 3489 3490 if (PrevTypedef && isDeclInScope(PrevTypedef, SearchDC, S) && 3491 Context.getCanonicalType(Context.getTypeDeclType(PrevTypedef)) != 3492 Context.getCanonicalType(Context.getTypeDeclType(New))) { 3493 Diag(Loc, diag::err_tag_definition_of_typedef) 3494 << Context.getTypeDeclType(New) 3495 << PrevTypedef->getUnderlyingType(); 3496 Diag(PrevTypedef->getLocation(), diag::note_previous_definition); 3497 Invalid = true; 3498 } 3499 } 3500 3501 if (Invalid) 3502 New->setInvalidDecl(); 3503 3504 if (Attr) 3505 ProcessDeclAttributeList(New, Attr); 3506 3507 // If we're declaring or defining a tag in function prototype scope 3508 // in C, note that this type can only be used within the function. 3509 if (Name && S->isFunctionPrototypeScope() && !getLangOptions().CPlusPlus) 3510 Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New); 3511 3512 // Set the lexical context. If the tag has a C++ scope specifier, the 3513 // lexical context will be different from the semantic context. 3514 New->setLexicalDeclContext(CurContext); 3515 3516 // Set the access specifier. 3517 SetMemberAccessSpecifier(New, PrevDecl, AS); 3518 3519 if (TK == TK_Definition) 3520 New->startDefinition(); 3521 3522 // If this has an identifier, add it to the scope stack. 3523 if (Name) { 3524 S = getNonFieldDeclScope(S); 3525 PushOnScopeChains(New, S); 3526 } else { 3527 CurContext->addDecl(Context, New); 3528 } 3529 3530 return DeclPtrTy::make(New); 3531} 3532 3533void Sema::ActOnTagStartDefinition(Scope *S, DeclPtrTy TagD) { 3534 AdjustDeclIfTemplate(TagD); 3535 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3536 3537 // Enter the tag context. 3538 PushDeclContext(S, Tag); 3539 3540 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Tag)) { 3541 FieldCollector->StartClass(); 3542 3543 if (Record->getIdentifier()) { 3544 // C++ [class]p2: 3545 // [...] The class-name is also inserted into the scope of the 3546 // class itself; this is known as the injected-class-name. For 3547 // purposes of access checking, the injected-class-name is treated 3548 // as if it were a public member name. 3549 CXXRecordDecl *InjectedClassName 3550 = CXXRecordDecl::Create(Context, Record->getTagKind(), 3551 CurContext, Record->getLocation(), 3552 Record->getIdentifier(), Record); 3553 InjectedClassName->setImplicit(); 3554 InjectedClassName->setAccess(AS_public); 3555 if (ClassTemplateDecl *Template = Record->getDescribedClassTemplate()) 3556 InjectedClassName->setDescribedClassTemplate(Template); 3557 PushOnScopeChains(InjectedClassName, S); 3558 assert(InjectedClassName->isInjectedClassName() && 3559 "Broken injected-class-name"); 3560 } 3561 } 3562} 3563 3564void Sema::ActOnTagFinishDefinition(Scope *S, DeclPtrTy TagD) { 3565 AdjustDeclIfTemplate(TagD); 3566 TagDecl *Tag = cast<TagDecl>(TagD.getAs<Decl>()); 3567 3568 if (isa<CXXRecordDecl>(Tag)) 3569 FieldCollector->FinishClass(); 3570 3571 // Exit this scope of this tag's definition. 3572 PopDeclContext(); 3573 3574 // Notify the consumer that we've defined a tag. 3575 Consumer.HandleTagDeclDefinition(Tag); 3576} 3577 3578bool Sema::VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName, 3579 QualType FieldTy, const Expr *BitWidth) { 3580 // C99 6.7.2.1p4 - verify the field type. 3581 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 3582 if (!FieldTy->isDependentType() && !FieldTy->isIntegralType()) { 3583 // Handle incomplete types with specific error. 3584 if (RequireCompleteType(FieldLoc, FieldTy, diag::err_field_incomplete)) 3585 return true; 3586 return Diag(FieldLoc, diag::err_not_integral_type_bitfield) 3587 << FieldName << FieldTy << BitWidth->getSourceRange(); 3588 } 3589 3590 // If the bit-width is type- or value-dependent, don't try to check 3591 // it now. 3592 if (BitWidth->isValueDependent() || BitWidth->isTypeDependent()) 3593 return false; 3594 3595 llvm::APSInt Value; 3596 if (VerifyIntegerConstantExpression(BitWidth, &Value)) 3597 return true; 3598 3599 // Zero-width bitfield is ok for anonymous field. 3600 if (Value == 0 && FieldName) 3601 return Diag(FieldLoc, diag::err_bitfield_has_zero_width) << FieldName; 3602 3603 if (Value.isSigned() && Value.isNegative()) 3604 return Diag(FieldLoc, diag::err_bitfield_has_negative_width) 3605 << FieldName << Value.toString(10); 3606 3607 if (!FieldTy->isDependentType()) { 3608 uint64_t TypeSize = Context.getTypeSize(FieldTy); 3609 // FIXME: We won't need the 0 size once we check that the field type is valid. 3610 if (TypeSize && Value.getZExtValue() > TypeSize) 3611 return Diag(FieldLoc, diag::err_bitfield_width_exceeds_type_size) 3612 << FieldName << (unsigned)TypeSize; 3613 } 3614 3615 return false; 3616} 3617 3618/// ActOnField - Each field of a struct/union/class is passed into this in order 3619/// to create a FieldDecl object for it. 3620Sema::DeclPtrTy Sema::ActOnField(Scope *S, DeclPtrTy TagD, 3621 SourceLocation DeclStart, 3622 Declarator &D, ExprTy *BitfieldWidth) { 3623 FieldDecl *Res = HandleField(S, cast_or_null<RecordDecl>(TagD.getAs<Decl>()), 3624 DeclStart, D, static_cast<Expr*>(BitfieldWidth), 3625 AS_public); 3626 return DeclPtrTy::make(Res); 3627} 3628 3629/// HandleField - Analyze a field of a C struct or a C++ data member. 3630/// 3631FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record, 3632 SourceLocation DeclStart, 3633 Declarator &D, Expr *BitWidth, 3634 AccessSpecifier AS) { 3635 IdentifierInfo *II = D.getIdentifier(); 3636 SourceLocation Loc = DeclStart; 3637 if (II) Loc = D.getIdentifierLoc(); 3638 3639 QualType T = GetTypeForDeclarator(D, S); 3640 if (getLangOptions().CPlusPlus) 3641 CheckExtraCXXDefaultArguments(D); 3642 3643 DiagnoseFunctionSpecifiers(D); 3644 3645 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3646 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S)) 3647 PrevDecl = 0; 3648 3649 FieldDecl *NewFD 3650 = CheckFieldDecl(II, T, Record, Loc, 3651 D.getDeclSpec().getStorageClassSpec() == DeclSpec::SCS_mutable, 3652 BitWidth, AS, PrevDecl, &D); 3653 if (NewFD->isInvalidDecl() && PrevDecl) { 3654 // Don't introduce NewFD into scope; there's already something 3655 // with the same name in the same scope. 3656 } else if (II) { 3657 PushOnScopeChains(NewFD, S); 3658 } else 3659 Record->addDecl(Context, NewFD); 3660 3661 return NewFD; 3662} 3663 3664/// \brief Build a new FieldDecl and check its well-formedness. 3665/// 3666/// This routine builds a new FieldDecl given the fields name, type, 3667/// record, etc. \p PrevDecl should refer to any previous declaration 3668/// with the same name and in the same scope as the field to be 3669/// created. 3670/// 3671/// \returns a new FieldDecl. 3672/// 3673/// \todo The Declarator argument is a hack. It will be removed once 3674FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T, 3675 RecordDecl *Record, SourceLocation Loc, 3676 bool Mutable, Expr *BitWidth, 3677 AccessSpecifier AS, NamedDecl *PrevDecl, 3678 Declarator *D) { 3679 IdentifierInfo *II = Name.getAsIdentifierInfo(); 3680 bool InvalidDecl = false; 3681 3682 // If we receive a broken type, recover by assuming 'int' and 3683 // marking this declaration as invalid. 3684 if (T.isNull()) { 3685 InvalidDecl = true; 3686 T = Context.IntTy; 3687 } 3688 3689 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3690 // than a variably modified type. 3691 if (T->isVariablyModifiedType()) { 3692 bool SizeIsNegative; 3693 QualType FixedTy = TryToFixInvalidVariablyModifiedType(T, Context, 3694 SizeIsNegative); 3695 if (!FixedTy.isNull()) { 3696 Diag(Loc, diag::warn_illegal_constant_array_size); 3697 T = FixedTy; 3698 } else { 3699 if (SizeIsNegative) 3700 Diag(Loc, diag::err_typecheck_negative_array_size); 3701 else 3702 Diag(Loc, diag::err_typecheck_field_variable_size); 3703 T = Context.IntTy; 3704 InvalidDecl = true; 3705 } 3706 } 3707 3708 // Fields can not have abstract class types 3709 if (RequireNonAbstractType(Loc, T, diag::err_abstract_type_in_decl, 3710 AbstractFieldType)) 3711 InvalidDecl = true; 3712 3713 // If this is declared as a bit-field, check the bit-field. 3714 if (BitWidth && VerifyBitField(Loc, II, T, BitWidth)) { 3715 InvalidDecl = true; 3716 DeleteExpr(BitWidth); 3717 BitWidth = 0; 3718 } 3719 3720 FieldDecl *NewFD = FieldDecl::Create(Context, Record, Loc, II, T, BitWidth, 3721 Mutable); 3722 3723 if (PrevDecl && !isa<TagDecl>(PrevDecl)) { 3724 Diag(Loc, diag::err_duplicate_member) << II; 3725 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3726 NewFD->setInvalidDecl(); 3727 Record->setInvalidDecl(); 3728 } 3729 3730 if (getLangOptions().CPlusPlus && !T->isPODType()) 3731 cast<CXXRecordDecl>(Record)->setPOD(false); 3732 3733 // FIXME: We need to pass in the attributes given an AST 3734 // representation, not a parser representation. 3735 if (D) 3736 ProcessDeclAttributes(NewFD, *D); 3737 3738 if (T.isObjCGCWeak()) 3739 Diag(Loc, diag::warn_attribute_weak_on_field); 3740 3741 if (InvalidDecl) 3742 NewFD->setInvalidDecl(); 3743 3744 NewFD->setAccess(AS); 3745 3746 // C++ [dcl.init.aggr]p1: 3747 // An aggregate is an array or a class (clause 9) with [...] no 3748 // private or protected non-static data members (clause 11). 3749 // A POD must be an aggregate. 3750 if (getLangOptions().CPlusPlus && 3751 (AS == AS_private || AS == AS_protected)) { 3752 CXXRecordDecl *CXXRecord = cast<CXXRecordDecl>(Record); 3753 CXXRecord->setAggregate(false); 3754 CXXRecord->setPOD(false); 3755 } 3756 3757 return NewFD; 3758} 3759 3760/// TranslateIvarVisibility - Translate visibility from a token ID to an 3761/// AST enum value. 3762static ObjCIvarDecl::AccessControl 3763TranslateIvarVisibility(tok::ObjCKeywordKind ivarVisibility) { 3764 switch (ivarVisibility) { 3765 default: assert(0 && "Unknown visitibility kind"); 3766 case tok::objc_private: return ObjCIvarDecl::Private; 3767 case tok::objc_public: return ObjCIvarDecl::Public; 3768 case tok::objc_protected: return ObjCIvarDecl::Protected; 3769 case tok::objc_package: return ObjCIvarDecl::Package; 3770 } 3771} 3772 3773/// ActOnIvar - Each ivar field of an objective-c class is passed into this 3774/// in order to create an IvarDecl object for it. 3775Sema::DeclPtrTy Sema::ActOnIvar(Scope *S, 3776 SourceLocation DeclStart, 3777 Declarator &D, ExprTy *BitfieldWidth, 3778 tok::ObjCKeywordKind Visibility) { 3779 3780 IdentifierInfo *II = D.getIdentifier(); 3781 Expr *BitWidth = (Expr*)BitfieldWidth; 3782 SourceLocation Loc = DeclStart; 3783 if (II) Loc = D.getIdentifierLoc(); 3784 3785 // FIXME: Unnamed fields can be handled in various different ways, for 3786 // example, unnamed unions inject all members into the struct namespace! 3787 3788 QualType T = GetTypeForDeclarator(D, S); 3789 bool InvalidDecl = false; 3790 if (T.isNull()) { 3791 InvalidDecl = true; 3792 T = Context.IntTy; 3793 } 3794 3795 if (BitWidth) { 3796 // 6.7.2.1p3, 6.7.2.1p4 3797 if (VerifyBitField(Loc, II, T, BitWidth)) { 3798 InvalidDecl = true; 3799 DeleteExpr(BitWidth); 3800 BitWidth = 0; 3801 } 3802 } else { 3803 // Not a bitfield. 3804 3805 // validate II. 3806 3807 } 3808 3809 // C99 6.7.2.1p8: A member of a structure or union may have any type other 3810 // than a variably modified type. 3811 if (T->isVariablyModifiedType()) { 3812 Diag(Loc, diag::err_typecheck_ivar_variable_size); 3813 InvalidDecl = true; 3814 } 3815 3816 // Get the visibility (access control) for this ivar. 3817 ObjCIvarDecl::AccessControl ac = 3818 Visibility != tok::objc_not_keyword ? TranslateIvarVisibility(Visibility) 3819 : ObjCIvarDecl::None; 3820 3821 // Construct the decl. 3822 ObjCIvarDecl *NewID = ObjCIvarDecl::Create(Context, CurContext, Loc, II, T,ac, 3823 (Expr *)BitfieldWidth); 3824 3825 if (II) { 3826 NamedDecl *PrevDecl = LookupName(S, II, LookupMemberName, true); 3827 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, S) 3828 && !isa<TagDecl>(PrevDecl)) { 3829 Diag(Loc, diag::err_duplicate_member) << II; 3830 Diag(PrevDecl->getLocation(), diag::note_previous_declaration); 3831 NewID->setInvalidDecl(); 3832 } 3833 } 3834 3835 // Process attributes attached to the ivar. 3836 ProcessDeclAttributes(NewID, D); 3837 3838 if (D.getInvalidType() || InvalidDecl) 3839 NewID->setInvalidDecl(); 3840 3841 if (II) { 3842 // FIXME: When interfaces are DeclContexts, we'll need to add 3843 // these to the interface. 3844 S->AddDecl(DeclPtrTy::make(NewID)); 3845 IdResolver.AddDecl(NewID); 3846 } 3847 3848 return DeclPtrTy::make(NewID); 3849} 3850 3851void Sema::ActOnFields(Scope* S, 3852 SourceLocation RecLoc, DeclPtrTy RecDecl, 3853 DeclPtrTy *Fields, unsigned NumFields, 3854 SourceLocation LBrac, SourceLocation RBrac, 3855 AttributeList *Attr) { 3856 Decl *EnclosingDecl = RecDecl.getAs<Decl>(); 3857 assert(EnclosingDecl && "missing record or interface decl"); 3858 3859 // If the decl this is being inserted into is invalid, then it may be a 3860 // redeclaration or some other bogus case. Don't try to add fields to it. 3861 if (EnclosingDecl->isInvalidDecl()) { 3862 // FIXME: Deallocate fields? 3863 return; 3864 } 3865 3866 3867 // Verify that all the fields are okay. 3868 unsigned NumNamedMembers = 0; 3869 llvm::SmallVector<FieldDecl*, 32> RecFields; 3870 3871 RecordDecl *Record = dyn_cast<RecordDecl>(EnclosingDecl); 3872 for (unsigned i = 0; i != NumFields; ++i) { 3873 FieldDecl *FD = cast<FieldDecl>(Fields[i].getAs<Decl>()); 3874 3875 // Get the type for the field. 3876 Type *FDTy = FD->getType().getTypePtr(); 3877 3878 if (!FD->isAnonymousStructOrUnion()) { 3879 // Remember all fields written by the user. 3880 RecFields.push_back(FD); 3881 } 3882 3883 // If the field is already invalid for some reason, don't emit more 3884 // diagnostics about it. 3885 if (FD->isInvalidDecl()) 3886 continue; 3887 3888 // C99 6.7.2.1p2: 3889 // A structure or union shall not contain a member with 3890 // incomplete or function type (hence, a structure shall not 3891 // contain an instance of itself, but may contain a pointer to 3892 // an instance of itself), except that the last member of a 3893 // structure with more than one named member may have incomplete 3894 // array type; such a structure (and any union containing, 3895 // possibly recursively, a member that is such a structure) 3896 // shall not be a member of a structure or an element of an 3897 // array. 3898 if (FDTy->isFunctionType()) { 3899 // Field declared as a function. 3900 Diag(FD->getLocation(), diag::err_field_declared_as_function) 3901 << FD->getDeclName(); 3902 FD->setInvalidDecl(); 3903 EnclosingDecl->setInvalidDecl(); 3904 continue; 3905 } else if (FDTy->isIncompleteArrayType() && i == NumFields - 1 && 3906 Record && Record->isStruct()) { 3907 // Flexible array member. 3908 if (NumNamedMembers < 1) { 3909 Diag(FD->getLocation(), diag::err_flexible_array_empty_struct) 3910 << FD->getDeclName(); 3911 FD->setInvalidDecl(); 3912 EnclosingDecl->setInvalidDecl(); 3913 continue; 3914 } 3915 // Okay, we have a legal flexible array member at the end of the struct. 3916 if (Record) 3917 Record->setHasFlexibleArrayMember(true); 3918 } else if (!FDTy->isDependentType() && 3919 RequireCompleteType(FD->getLocation(), FD->getType(), 3920 diag::err_field_incomplete)) { 3921 // Incomplete type 3922 FD->setInvalidDecl(); 3923 EnclosingDecl->setInvalidDecl(); 3924 continue; 3925 } else if (const RecordType *FDTTy = FDTy->getAsRecordType()) { 3926 if (FDTTy->getDecl()->hasFlexibleArrayMember()) { 3927 // If this is a member of a union, then entire union becomes "flexible". 3928 if (Record && Record->isUnion()) { 3929 Record->setHasFlexibleArrayMember(true); 3930 } else { 3931 // If this is a struct/class and this is not the last element, reject 3932 // it. Note that GCC supports variable sized arrays in the middle of 3933 // structures. 3934 if (i != NumFields-1) 3935 Diag(FD->getLocation(), diag::ext_variable_sized_type_in_struct) 3936 << FD->getDeclName(); 3937 else { 3938 // We support flexible arrays at the end of structs in 3939 // other structs as an extension. 3940 Diag(FD->getLocation(), diag::ext_flexible_array_in_struct) 3941 << FD->getDeclName(); 3942 if (Record) 3943 Record->setHasFlexibleArrayMember(true); 3944 } 3945 } 3946 } 3947 } else if (FDTy->isObjCInterfaceType()) { 3948 /// A field cannot be an Objective-c object 3949 Diag(FD->getLocation(), diag::err_statically_allocated_object); 3950 FD->setInvalidDecl(); 3951 EnclosingDecl->setInvalidDecl(); 3952 continue; 3953 } 3954 // Keep track of the number of named members. 3955 if (FD->getIdentifier()) 3956 ++NumNamedMembers; 3957 } 3958 3959 // Okay, we successfully defined 'Record'. 3960 if (Record) { 3961 Record->completeDefinition(Context); 3962 } else { 3963 ObjCIvarDecl **ClsFields = reinterpret_cast<ObjCIvarDecl**>(&RecFields[0]); 3964 if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(EnclosingDecl)) { 3965 ID->setIVarList(ClsFields, RecFields.size(), Context); 3966 ID->setLocEnd(RBrac); 3967 3968 // Must enforce the rule that ivars in the base classes may not be 3969 // duplicates. 3970 if (ID->getSuperClass()) { 3971 for (ObjCInterfaceDecl::ivar_iterator IVI = ID->ivar_begin(), 3972 IVE = ID->ivar_end(); IVI != IVE; ++IVI) { 3973 ObjCIvarDecl* Ivar = (*IVI); 3974 IdentifierInfo *II = Ivar->getIdentifier(); 3975 ObjCIvarDecl* prevIvar = 3976 ID->getSuperClass()->lookupInstanceVariable(Context, II); 3977 if (prevIvar) { 3978 Diag(Ivar->getLocation(), diag::err_duplicate_member) << II; 3979 Diag(prevIvar->getLocation(), diag::note_previous_declaration); 3980 } 3981 } 3982 } 3983 } else if (ObjCImplementationDecl *IMPDecl = 3984 dyn_cast<ObjCImplementationDecl>(EnclosingDecl)) { 3985 assert(IMPDecl && "ActOnFields - missing ObjCImplementationDecl"); 3986 IMPDecl->setIVarList(ClsFields, RecFields.size(), Context); 3987 CheckImplementationIvars(IMPDecl, ClsFields, RecFields.size(), RBrac); 3988 } 3989 } 3990 3991 if (Attr) 3992 ProcessDeclAttributeList(Record, Attr); 3993} 3994 3995EnumConstantDecl *Sema::CheckEnumConstant(EnumDecl *Enum, 3996 EnumConstantDecl *LastEnumConst, 3997 SourceLocation IdLoc, 3998 IdentifierInfo *Id, 3999 ExprArg val) { 4000 Expr *Val = (Expr *)val.get(); 4001 4002 llvm::APSInt EnumVal(32); 4003 QualType EltTy; 4004 if (Val && !Val->isTypeDependent()) { 4005 // Make sure to promote the operand type to int. 4006 UsualUnaryConversions(Val); 4007 if (Val != val.get()) { 4008 val.release(); 4009 val = Val; 4010 } 4011 4012 // C99 6.7.2.2p2: Make sure we have an integer constant expression. 4013 SourceLocation ExpLoc; 4014 if (!Val->isValueDependent() && 4015 VerifyIntegerConstantExpression(Val, &EnumVal)) { 4016 Val = 0; 4017 } else { 4018 EltTy = Val->getType(); 4019 } 4020 } 4021 4022 if (!Val) { 4023 if (LastEnumConst) { 4024 // Assign the last value + 1. 4025 EnumVal = LastEnumConst->getInitVal(); 4026 ++EnumVal; 4027 4028 // Check for overflow on increment. 4029 if (EnumVal < LastEnumConst->getInitVal()) 4030 Diag(IdLoc, diag::warn_enum_value_overflow); 4031 4032 EltTy = LastEnumConst->getType(); 4033 } else { 4034 // First value, set to zero. 4035 EltTy = Context.IntTy; 4036 EnumVal.zextOrTrunc(static_cast<uint32_t>(Context.getTypeSize(EltTy))); 4037 } 4038 } 4039 4040 val.release(); 4041 return EnumConstantDecl::Create(Context, Enum, IdLoc, Id, EltTy, 4042 Val, EnumVal); 4043} 4044 4045 4046Sema::DeclPtrTy Sema::ActOnEnumConstant(Scope *S, DeclPtrTy theEnumDecl, 4047 DeclPtrTy lastEnumConst, 4048 SourceLocation IdLoc, 4049 IdentifierInfo *Id, 4050 SourceLocation EqualLoc, ExprTy *val) { 4051 EnumDecl *TheEnumDecl = cast<EnumDecl>(theEnumDecl.getAs<Decl>()); 4052 EnumConstantDecl *LastEnumConst = 4053 cast_or_null<EnumConstantDecl>(lastEnumConst.getAs<Decl>()); 4054 Expr *Val = static_cast<Expr*>(val); 4055 4056 // The scope passed in may not be a decl scope. Zip up the scope tree until 4057 // we find one that is. 4058 S = getNonFieldDeclScope(S); 4059 4060 // Verify that there isn't already something declared with this name in this 4061 // scope. 4062 NamedDecl *PrevDecl = LookupName(S, Id, LookupOrdinaryName); 4063 if (PrevDecl && PrevDecl->isTemplateParameter()) { 4064 // Maybe we will complain about the shadowed template parameter. 4065 DiagnoseTemplateParameterShadow(IdLoc, PrevDecl); 4066 // Just pretend that we didn't see the previous declaration. 4067 PrevDecl = 0; 4068 } 4069 4070 if (PrevDecl) { 4071 // When in C++, we may get a TagDecl with the same name; in this case the 4072 // enum constant will 'hide' the tag. 4073 assert((getLangOptions().CPlusPlus || !isa<TagDecl>(PrevDecl)) && 4074 "Received TagDecl when not in C++!"); 4075 if (!isa<TagDecl>(PrevDecl) && isDeclInScope(PrevDecl, CurContext, S)) { 4076 if (isa<EnumConstantDecl>(PrevDecl)) 4077 Diag(IdLoc, diag::err_redefinition_of_enumerator) << Id; 4078 else 4079 Diag(IdLoc, diag::err_redefinition) << Id; 4080 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 4081 if (Val) Val->Destroy(Context); 4082 return DeclPtrTy(); 4083 } 4084 } 4085 4086 EnumConstantDecl *New = CheckEnumConstant(TheEnumDecl, LastEnumConst, 4087 IdLoc, Id, Owned(Val)); 4088 4089 // Register this decl in the current scope stack. 4090 if (New) 4091 PushOnScopeChains(New, S); 4092 4093 return DeclPtrTy::make(New); 4094} 4095 4096// FIXME: For consistency with ActOnFields(), we should have the parser 4097// pass in the source location for the left/right braces. 4098void Sema::ActOnEnumBody(SourceLocation EnumLoc, DeclPtrTy EnumDeclX, 4099 DeclPtrTy *Elements, unsigned NumElements) { 4100 EnumDecl *Enum = cast<EnumDecl>(EnumDeclX.getAs<Decl>()); 4101 QualType EnumType = Context.getTypeDeclType(Enum); 4102 4103 // TODO: If the result value doesn't fit in an int, it must be a long or long 4104 // long value. ISO C does not support this, but GCC does as an extension, 4105 // emit a warning. 4106 unsigned IntWidth = Context.Target.getIntWidth(); 4107 4108 // Verify that all the values are okay, compute the size of the values, and 4109 // reverse the list. 4110 unsigned NumNegativeBits = 0; 4111 unsigned NumPositiveBits = 0; 4112 4113 // Keep track of whether all elements have type int. 4114 bool AllElementsInt = true; 4115 4116 for (unsigned i = 0; i != NumElements; ++i) { 4117 EnumConstantDecl *ECD = 4118 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4119 if (!ECD) continue; // Already issued a diagnostic. 4120 4121 // If the enum value doesn't fit in an int, emit an extension warning. 4122 const llvm::APSInt &InitVal = ECD->getInitVal(); 4123 assert(InitVal.getBitWidth() >= IntWidth && 4124 "Should have promoted value to int"); 4125 if (InitVal.getBitWidth() > IntWidth) { 4126 llvm::APSInt V(InitVal); 4127 V.trunc(IntWidth); 4128 V.extend(InitVal.getBitWidth()); 4129 if (V != InitVal) 4130 Diag(ECD->getLocation(), diag::ext_enum_value_not_int) 4131 << InitVal.toString(10); 4132 } 4133 4134 // Keep track of the size of positive and negative values. 4135 if (InitVal.isUnsigned() || InitVal.isNonNegative()) 4136 NumPositiveBits = std::max(NumPositiveBits, 4137 (unsigned)InitVal.getActiveBits()); 4138 else 4139 NumNegativeBits = std::max(NumNegativeBits, 4140 (unsigned)InitVal.getMinSignedBits()); 4141 4142 // Keep track of whether every enum element has type int (very commmon). 4143 if (AllElementsInt) 4144 AllElementsInt = ECD->getType() == Context.IntTy; 4145 } 4146 4147 // Figure out the type that should be used for this enum. 4148 // FIXME: Support attribute(packed) on enums and -fshort-enums. 4149 QualType BestType; 4150 unsigned BestWidth; 4151 4152 if (NumNegativeBits) { 4153 // If there is a negative value, figure out the smallest integer type (of 4154 // int/long/longlong) that fits. 4155 if (NumNegativeBits <= IntWidth && NumPositiveBits < IntWidth) { 4156 BestType = Context.IntTy; 4157 BestWidth = IntWidth; 4158 } else { 4159 BestWidth = Context.Target.getLongWidth(); 4160 4161 if (NumNegativeBits <= BestWidth && NumPositiveBits < BestWidth) 4162 BestType = Context.LongTy; 4163 else { 4164 BestWidth = Context.Target.getLongLongWidth(); 4165 4166 if (NumNegativeBits > BestWidth || NumPositiveBits >= BestWidth) 4167 Diag(Enum->getLocation(), diag::warn_enum_too_large); 4168 BestType = Context.LongLongTy; 4169 } 4170 } 4171 } else { 4172 // If there is no negative value, figure out which of uint, ulong, ulonglong 4173 // fits. 4174 if (NumPositiveBits <= IntWidth) { 4175 BestType = Context.UnsignedIntTy; 4176 BestWidth = IntWidth; 4177 } else if (NumPositiveBits <= 4178 (BestWidth = Context.Target.getLongWidth())) { 4179 BestType = Context.UnsignedLongTy; 4180 } else { 4181 BestWidth = Context.Target.getLongLongWidth(); 4182 assert(NumPositiveBits <= BestWidth && 4183 "How could an initializer get larger than ULL?"); 4184 BestType = Context.UnsignedLongLongTy; 4185 } 4186 } 4187 4188 // Loop over all of the enumerator constants, changing their types to match 4189 // the type of the enum if needed. 4190 for (unsigned i = 0; i != NumElements; ++i) { 4191 EnumConstantDecl *ECD = 4192 cast_or_null<EnumConstantDecl>(Elements[i].getAs<Decl>()); 4193 if (!ECD) continue; // Already issued a diagnostic. 4194 4195 // Standard C says the enumerators have int type, but we allow, as an 4196 // extension, the enumerators to be larger than int size. If each 4197 // enumerator value fits in an int, type it as an int, otherwise type it the 4198 // same as the enumerator decl itself. This means that in "enum { X = 1U }" 4199 // that X has type 'int', not 'unsigned'. 4200 if (ECD->getType() == Context.IntTy) { 4201 // Make sure the init value is signed. 4202 llvm::APSInt IV = ECD->getInitVal(); 4203 IV.setIsSigned(true); 4204 ECD->setInitVal(IV); 4205 4206 if (getLangOptions().CPlusPlus) 4207 // C++ [dcl.enum]p4: Following the closing brace of an 4208 // enum-specifier, each enumerator has the type of its 4209 // enumeration. 4210 ECD->setType(EnumType); 4211 continue; // Already int type. 4212 } 4213 4214 // Determine whether the value fits into an int. 4215 llvm::APSInt InitVal = ECD->getInitVal(); 4216 bool FitsInInt; 4217 if (InitVal.isUnsigned() || !InitVal.isNegative()) 4218 FitsInInt = InitVal.getActiveBits() < IntWidth; 4219 else 4220 FitsInInt = InitVal.getMinSignedBits() <= IntWidth; 4221 4222 // If it fits into an integer type, force it. Otherwise force it to match 4223 // the enum decl type. 4224 QualType NewTy; 4225 unsigned NewWidth; 4226 bool NewSign; 4227 if (FitsInInt) { 4228 NewTy = Context.IntTy; 4229 NewWidth = IntWidth; 4230 NewSign = true; 4231 } else if (ECD->getType() == BestType) { 4232 // Already the right type! 4233 if (getLangOptions().CPlusPlus) 4234 // C++ [dcl.enum]p4: Following the closing brace of an 4235 // enum-specifier, each enumerator has the type of its 4236 // enumeration. 4237 ECD->setType(EnumType); 4238 continue; 4239 } else { 4240 NewTy = BestType; 4241 NewWidth = BestWidth; 4242 NewSign = BestType->isSignedIntegerType(); 4243 } 4244 4245 // Adjust the APSInt value. 4246 InitVal.extOrTrunc(NewWidth); 4247 InitVal.setIsSigned(NewSign); 4248 ECD->setInitVal(InitVal); 4249 4250 // Adjust the Expr initializer and type. 4251 if (ECD->getInitExpr()) 4252 ECD->setInitExpr(new (Context) ImplicitCastExpr(NewTy, ECD->getInitExpr(), 4253 /*isLvalue=*/false)); 4254 if (getLangOptions().CPlusPlus) 4255 // C++ [dcl.enum]p4: Following the closing brace of an 4256 // enum-specifier, each enumerator has the type of its 4257 // enumeration. 4258 ECD->setType(EnumType); 4259 else 4260 ECD->setType(NewTy); 4261 } 4262 4263 Enum->completeDefinition(Context, BestType); 4264} 4265 4266Sema::DeclPtrTy Sema::ActOnFileScopeAsmDecl(SourceLocation Loc, 4267 ExprArg expr) { 4268 StringLiteral *AsmString = cast<StringLiteral>((Expr*)expr.release()); 4269 4270 return DeclPtrTy::make(FileScopeAsmDecl::Create(Context, CurContext, 4271 Loc, AsmString)); 4272} 4273 4274